Strings.ipynb

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello World\n"
     ]
    }
   ],
   "source": [
    "# printing a string message\n",
    "my_message = 'Hello World'\n",
    "print(my_message) "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello World\n"
     ]
    }
   ],
   "source": [
    "# using double quotes\n",
    "my_message = \"Hello World\"\n",
    "print(my_message)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello 'World'\n"
     ]
    }
   ],
   "source": [
    "# using both single inside double\n",
    "my_message = \"Hello 'World'\" \n",
    "print(my_message)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello 'World'\n"
     ]
    }
   ],
   "source": [
    "# using both double inside single\n",
    "my_message = 'Hello \"World\"'\n",
    "print(my_message)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "ename": "SyntaxError",
     "evalue": "invalid syntax (<ipython-input-7-cbeb1f4e4e43>, line 2)",
     "output_type": "error",
     "traceback": [
      "\u001b[1;36m  File \u001b[1;32m\"<ipython-input-7-cbeb1f4e4e43>\"\u001b[1;36m, line \u001b[1;32m2\u001b[0m\n\u001b[1;33m    my_dog = 'Sumit's dog'\u001b[0m\n\u001b[1;37m                    ^\u001b[0m\n\u001b[1;31mSyntaxError\u001b[0m\u001b[1;31m:\u001b[0m invalid syntax\n"
     ]
    }
   ],
   "source": [
    "# concept of escaping next character\n",
    "my_dog = 'Sumit's dog'\n",
    "print(my_dog)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Sumit's Dog\n"
     ]
    }
   ],
   "source": [
    "# oops we got synatax error as <'> this is closing the string\n",
    "# to solve this problem we can use escape \n",
    "my_dog = 'Sumit\\'s Dog'\n",
    "print(my_dog)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Sumit's Cat\n"
     ]
    }
   ],
   "source": [
    "# here it works fine for double quotes\n",
    "my_cat = \"Sumit's Cat\"\n",
    "print(my_cat)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      " Shaktiman was good fiction\n",
      "                play in 1990's for all.\n",
      "\n"
     ]
    }
   ],
   "source": [
    "# what if we want to print string same as it is in console\n",
    "# here we can use \"\"\" string \"\"\"\"\n",
    "my_carton = \"\"\" Shaktiman was good fiction\n",
    "                play in 1990's for all.\n",
    "\"\"\"\n",
    "print(my_carton)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "11\n"
     ]
    }
   ],
   "source": [
    "# to get length of the string\n",
    "# use len() function for this\n",
    "my_message = 'Hello World'\n",
    "print(len(my_message))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "H\n",
      "e\n",
      "d\n"
     ]
    }
   ],
   "source": [
    "# how to access string by its index, my_message[index:starts from 0 to (len()-1)]\n",
    "print(my_message[0]) # character at 0th index\n",
    "print(my_message[1]) # character at 1st index\n",
    "print(my_message[len(my_message)-1]) # character at last'th index"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {},
   "outputs": [
    {
     "ename": "IndexError",
     "evalue": "string index out of range",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mIndexError\u001b[0m                                Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-24-718eba65d355>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[1;31m# if you pass index greater than its (length-1)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 2\u001b[1;33m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mmy_message\u001b[0m\u001b[1;33m[\u001b[0m\u001b[0mlen\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mmy_message\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mIndexError\u001b[0m: string index out of range"
     ]
    }
   ],
   "source": [
    "# if you pass index greater than its (length-1)\n",
    "# you will get error <string index out of range>\n",
    "print(my_message[len(my_message)]) # total number of characters+whitespace"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello\n"
     ]
    }
   ],
   "source": [
    "# concept of slicing string by string[start_index(0):end_index(5)]\n",
    "# here 0th index is inclusive but 5th index is exclusive\n",
    "my_message = 'Hello World'\n",
    "print(my_message[0:5])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello\n"
     ]
    }
   ],
   "source": [
    "# game 1\n",
    "# still getting same means if start_index is empty it takes 0th by default \n",
    "print(my_message[:5])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello World\n"
     ]
    }
   ],
   "source": [
    "# game 2\n",
    "# if end_index is empty it takes (length-1)th index by default \n",
    "print(my_message[0:])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello World\n"
     ]
    }
   ],
   "source": [
    "# game 3\n",
    "# what if both empty, curious!\n",
    "print(my_message[:])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Sumit Kumar'"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# reversing the string by using slicing\n",
    "name = 'ramuK timuS'\n",
    "name[::-1]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 32,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "d\n"
     ]
    }
   ],
   "source": [
    "# game 4\n",
    "# what if neagtive index, it loop back from last index\n",
    "#               0123456789 (forward indexing)\n",
    "# my_message = 'HelloWorld'\n",
    "#          -9-8-7-6-5-4-3-2-1 (backward indexing)\n",
    "my_message = 'HelloWorld'\n",
    "print(my_message[-1])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 49,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "\n"
     ]
    }
   ],
   "source": [
    "# game 5\n",
    "# reverse string using slicing\n",
    "print(my_message[-1:0])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 51,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "HELLOWORLD\n",
      "helloworld\n"
     ]
    }
   ],
   "source": [
    "# some functions for string upper(),lower()\n",
    "print(my_message.upper()) # my_message in upper case\n",
    "print(my_message.lower()) # my_message in lower case"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 53,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n",
      "3\n"
     ]
    }
   ],
   "source": [
    "# count the occurence of particular character/words in string\n",
    "print(my_message.count('Hello')) # 1 time occurence of 'hello' in my_message\n",
    "print(my_message.count('l')) # 3 times occurence of 'l' in my_message"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 59,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "6\n",
      "-1\n"
     ]
    }
   ],
   "source": [
    "# finding the start index use find()\n",
    "my_message = 'Hello World'\n",
    "print(my_message.find('World')) # W is at 6th index\n",
    "print(my_message.find('Not in string')) # return -1 as o/p"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 63,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello Universe\n"
     ]
    }
   ],
   "source": [
    "# replacing string with other\n",
    "my_message = 'Hello World'\n",
    "new_message = my_message.replace('World', 'Universe') # replacing 'World' with 'Universe'\n",
    "print(new_message)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 64,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello, Sumit\n"
     ]
    }
   ],
   "source": [
    "# conactenation of strings\n",
    "greet = 'Hello'\n",
    "name = 'Sumit'\n",
    "print(greet + ', ' + name)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 65,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello, Sumit. Welcome!\n"
     ]
    }
   ],
   "source": [
    "# .format() for conactenation \n",
    "greet = 'Hello'\n",
    "name = 'Sumit'\n",
    "print('{}, {}. Welcome!'.format(greet, name)) # more readable"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 69,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello, Sumit. Welcome!\n"
     ]
    }
   ],
   "source": [
    "# other way of formatting string\n",
    "greet = 'Hello'\n",
    "name = 'Sumit'\n",
    "print(f'{greet}, {name}. Welcome!') # more readable"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 71,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "HelloWorld HelloWorld HelloWorld HelloWorld HelloWorld \n"
     ]
    }
   ],
   "source": [
    "# multiplication of string\n",
    "my_message = 'HelloWorld '\n",
    "print(my_message * 5) # 5 times my_message"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 73,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "'str' object does not support item assignment",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-73-552e497b1d44>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[1;31m# strings are immutable, can't change\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      2\u001b[0m \u001b[1;31m# getting error <'str' object does not support item assignment>\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 3\u001b[1;33m \u001b[0mmy_message\u001b[0m\u001b[1;33m[\u001b[0m\u001b[1;36m0\u001b[0m\u001b[1;33m]\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;34m'M'\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m      4\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mmy_message\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31mTypeError\u001b[0m: 'str' object does not support item assignment"
     ]
    }
   ],
   "source": [
    "# strings are immutable, can't change\n",
    "# getting error <'str' object does not support item assignment>\n",
    "my_message[0] = 'M'\n",
    "print(my_message)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 74,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Help on class str in module builtins:\n",
      "\n",
      "class str(object)\n",
      " |  str(object='') -> str\n",
      " |  str(bytes_or_buffer[, encoding[, errors]]) -> str\n",
      " |  \n",
      " |  Create a new string object from the given object. If encoding or\n",
      " |  errors is specified, then the object must expose a data buffer\n",
      " |  that will be decoded using the given encoding and error handler.\n",
      " |  Otherwise, returns the result of object.__str__() (if defined)\n",
      " |  or repr(object).\n",
      " |  encoding defaults to sys.getdefaultencoding().\n",
      " |  errors defaults to 'strict'.\n",
      " |  \n",
      " |  Methods defined here:\n",
      " |  \n",
      " |  __add__(self, value, /)\n",
      " |      Return self+value.\n",
      " |  \n",
      " |  __contains__(self, key, /)\n",
      " |      Return key in self.\n",
      " |  \n",
      " |  __eq__(self, value, /)\n",
      " |      Return self==value.\n",
      " |  \n",
      " |  __format__(self, format_spec, /)\n",
      " |      Return a formatted version of the string as described by format_spec.\n",
      " |  \n",
      " |  __ge__(self, value, /)\n",
      " |      Return self>=value.\n",
      " |  \n",
      " |  __getattribute__(self, name, /)\n",
      " |      Return getattr(self, name).\n",
      " |  \n",
      " |  __getitem__(self, key, /)\n",
      " |      Return self[key].\n",
      " |  \n",
      " |  __getnewargs__(...)\n",
      " |  \n",
      " |  __gt__(self, value, /)\n",
      " |      Return self>value.\n",
      " |  \n",
      " |  __hash__(self, /)\n",
      " |      Return hash(self).\n",
      " |  \n",
      " |  __iter__(self, /)\n",
      " |      Implement iter(self).\n",
      " |  \n",
      " |  __le__(self, value, /)\n",
      " |      Return self<=value.\n",
      " |  \n",
      " |  __len__(self, /)\n",
      " |      Return len(self).\n",
      " |  \n",
      " |  __lt__(self, value, /)\n",
      " |      Return self<value.\n",
      " |  \n",
      " |  __mod__(self, value, /)\n",
      " |      Return self%value.\n",
      " |  \n",
      " |  __mul__(self, value, /)\n",
      " |      Return self*value.\n",
      " |  \n",
      " |  __ne__(self, value, /)\n",
      " |      Return self!=value.\n",
      " |  \n",
      " |  __repr__(self, /)\n",
      " |      Return repr(self).\n",
      " |  \n",
      " |  __rmod__(self, value, /)\n",
      " |      Return value%self.\n",
      " |  \n",
      " |  __rmul__(self, value, /)\n",
      " |      Return value*self.\n",
      " |  \n",
      " |  __sizeof__(self, /)\n",
      " |      Return the size of the string in memory, in bytes.\n",
      " |  \n",
      " |  __str__(self, /)\n",
      " |      Return str(self).\n",
      " |  \n",
      " |  capitalize(self, /)\n",
      " |      Return a capitalized version of the string.\n",
      " |      \n",
      " |      More specifically, make the first character have upper case and the rest lower\n",
      " |      case.\n",
      " |  \n",
      " |  casefold(self, /)\n",
      " |      Return a version of the string suitable for caseless comparisons.\n",
      " |  \n",
      " |  center(self, width, fillchar=' ', /)\n",
      " |      Return a centered string of length width.\n",
      " |      \n",
      " |      Padding is done using the specified fill character (default is a space).\n",
      " |  \n",
      " |  count(...)\n",
      " |      S.count(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the number of non-overlapping occurrences of substring sub in\n",
      " |      string S[start:end].  Optional arguments start and end are\n",
      " |      interpreted as in slice notation.\n",
      " |  \n",
      " |  encode(self, /, encoding='utf-8', errors='strict')\n",
      " |      Encode the string using the codec registered for encoding.\n",
      " |      \n",
      " |      encoding\n",
      " |        The encoding in which to encode the string.\n",
      " |      errors\n",
      " |        The error handling scheme to use for encoding errors.\n",
      " |        The default is 'strict' meaning that encoding errors raise a\n",
      " |        UnicodeEncodeError.  Other possible values are 'ignore', 'replace' and\n",
      " |        'xmlcharrefreplace' as well as any other name registered with\n",
      " |        codecs.register_error that can handle UnicodeEncodeErrors.\n",
      " |  \n",
      " |  endswith(...)\n",
      " |      S.endswith(suffix[, start[, end]]) -> bool\n",
      " |      \n",
      " |      Return True if S ends with the specified suffix, False otherwise.\n",
      " |      With optional start, test S beginning at that position.\n",
      " |      With optional end, stop comparing S at that position.\n",
      " |      suffix can also be a tuple of strings to try.\n",
      " |  \n",
      " |  expandtabs(self, /, tabsize=8)\n",
      " |      Return a copy where all tab characters are expanded using spaces.\n",
      " |      \n",
      " |      If tabsize is not given, a tab size of 8 characters is assumed.\n",
      " |  \n",
      " |  find(...)\n",
      " |      S.find(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the lowest index in S where substring sub is found,\n",
      " |      such that sub is contained within S[start:end].  Optional\n",
      " |      arguments start and end are interpreted as in slice notation.\n",
      " |      \n",
      " |      Return -1 on failure.\n",
      " |  \n",
      " |  format(...)\n",
      " |      S.format(*args, **kwargs) -> str\n",
      " |      \n",
      " |      Return a formatted version of S, using substitutions from args and kwargs.\n",
      " |      The substitutions are identified by braces ('{' and '}').\n",
      " |  \n",
      " |  format_map(...)\n",
      " |      S.format_map(mapping) -> str\n",
      " |      \n",
      " |      Return a formatted version of S, using substitutions from mapping.\n",
      " |      The substitutions are identified by braces ('{' and '}').\n",
      " |  \n",
      " |  index(...)\n",
      " |      S.index(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the lowest index in S where substring sub is found, \n",
      " |      such that sub is contained within S[start:end].  Optional\n",
      " |      arguments start and end are interpreted as in slice notation.\n",
      " |      \n",
      " |      Raises ValueError when the substring is not found.\n",
      " |  \n",
      " |  isalnum(self, /)\n",
      " |      Return True if the string is an alpha-numeric string, False otherwise.\n",
      " |      \n",
      " |      A string is alpha-numeric if all characters in the string are alpha-numeric and\n",
      " |      there is at least one character in the string.\n",
      " |  \n",
      " |  isalpha(self, /)\n",
      " |      Return True if the string is an alphabetic string, False otherwise.\n",
      " |      \n",
      " |      A string is alphabetic if all characters in the string are alphabetic and there\n",
      " |      is at least one character in the string.\n",
      " |  \n",
      " |  isascii(self, /)\n",
      " |      Return True if all characters in the string are ASCII, False otherwise.\n",
      " |      \n",
      " |      ASCII characters have code points in the range U+0000-U+007F.\n",
      " |      Empty string is ASCII too.\n",
      " |  \n",
      " |  isdecimal(self, /)\n",
      " |      Return True if the string is a decimal string, False otherwise.\n",
      " |      \n",
      " |      A string is a decimal string if all characters in the string are decimal and\n",
      " |      there is at least one character in the string.\n",
      " |  \n",
      " |  isdigit(self, /)\n",
      " |      Return True if the string is a digit string, False otherwise.\n",
      " |      \n",
      " |      A string is a digit string if all characters in the string are digits and there\n",
      " |      is at least one character in the string.\n",
      " |  \n",
      " |  isidentifier(self, /)\n",
      " |      Return True if the string is a valid Python identifier, False otherwise.\n",
      " |      \n",
      " |      Use keyword.iskeyword() to test for reserved identifiers such as \"def\" and\n",
      " |      \"class\".\n",
      " |  \n",
      " |  islower(self, /)\n",
      " |      Return True if the string is a lowercase string, False otherwise.\n",
      " |      \n",
      " |      A string is lowercase if all cased characters in the string are lowercase and\n",
      " |      there is at least one cased character in the string.\n",
      " |  \n",
      " |  isnumeric(self, /)\n",
      " |      Return True if the string is a numeric string, False otherwise.\n",
      " |      \n",
      " |      A string is numeric if all characters in the string are numeric and there is at\n",
      " |      least one character in the string.\n",
      " |  \n",
      " |  isprintable(self, /)\n",
      " |      Return True if the string is printable, False otherwise.\n",
      " |      \n",
      " |      A string is printable if all of its characters are considered printable in\n",
      " |      repr() or if it is empty.\n",
      " |  \n",
      " |  isspace(self, /)\n",
      " |      Return True if the string is a whitespace string, False otherwise.\n",
      " |      \n",
      " |      A string is whitespace if all characters in the string are whitespace and there\n",
      " |      is at least one character in the string.\n",
      " |  \n",
      " |  istitle(self, /)\n",
      " |      Return True if the string is a title-cased string, False otherwise.\n",
      " |      \n",
      " |      In a title-cased string, upper- and title-case characters may only\n",
      " |      follow uncased characters and lowercase characters only cased ones.\n",
      " |  \n",
      " |  isupper(self, /)\n",
      " |      Return True if the string is an uppercase string, False otherwise.\n",
      " |      \n",
      " |      A string is uppercase if all cased characters in the string are uppercase and\n",
      " |      there is at least one cased character in the string.\n",
      " |  \n",
      " |  join(self, iterable, /)\n",
      " |      Concatenate any number of strings.\n",
      " |      \n",
      " |      The string whose method is called is inserted in between each given string.\n",
      " |      The result is returned as a new string.\n",
      " |      \n",
      " |      Example: '.'.join(['ab', 'pq', 'rs']) -> 'ab.pq.rs'\n",
      " |  \n",
      " |  ljust(self, width, fillchar=' ', /)\n",
      " |      Return a left-justified string of length width.\n",
      " |      \n",
      " |      Padding is done using the specified fill character (default is a space).\n",
      " |  \n",
      " |  lower(self, /)\n",
      " |      Return a copy of the string converted to lowercase.\n",
      " |  \n",
      " |  lstrip(self, chars=None, /)\n",
      " |      Return a copy of the string with leading whitespace removed.\n",
      " |      \n",
      " |      If chars is given and not None, remove characters in chars instead.\n",
      " |  \n",
      " |  partition(self, sep, /)\n",
      " |      Partition the string into three parts using the given separator.\n",
      " |      \n",
      " |      This will search for the separator in the string.  If the separator is found,\n",
      " |      returns a 3-tuple containing the part before the separator, the separator\n",
      " |      itself, and the part after it.\n",
      " |      \n",
      " |      If the separator is not found, returns a 3-tuple containing the original string\n",
      " |      and two empty strings.\n",
      " |  \n",
      " |  replace(self, old, new, count=-1, /)\n",
      " |      Return a copy with all occurrences of substring old replaced by new.\n",
      " |      \n",
      " |        count\n",
      " |          Maximum number of occurrences to replace.\n",
      " |          -1 (the default value) means replace all occurrences.\n",
      " |      \n",
      " |      If the optional argument count is given, only the first count occurrences are\n",
      " |      replaced.\n",
      " |  \n",
      " |  rfind(...)\n",
      " |      S.rfind(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the highest index in S where substring sub is found,\n",
      " |      such that sub is contained within S[start:end].  Optional\n",
      " |      arguments start and end are interpreted as in slice notation.\n",
      " |      \n",
      " |      Return -1 on failure.\n",
      " |  \n",
      " |  rindex(...)\n",
      " |      S.rindex(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the highest index in S where substring sub is found,\n",
      " |      such that sub is contained within S[start:end].  Optional\n",
      " |      arguments start and end are interpreted as in slice notation.\n",
      " |      \n",
      " |      Raises ValueError when the substring is not found.\n",
      " |  \n",
      " |  rjust(self, width, fillchar=' ', /)\n",
      " |      Return a right-justified string of length width.\n",
      " |      \n",
      " |      Padding is done using the specified fill character (default is a space).\n",
      " |  \n",
      " |  rpartition(self, sep, /)\n",
      " |      Partition the string into three parts using the given separator.\n",
      " |      \n",
      " |      This will search for the separator in the string, starting at the end. If\n",
      " |      the separator is found, returns a 3-tuple containing the part before the\n",
      " |      separator, the separator itself, and the part after it.\n",
      " |      \n",
      " |      If the separator is not found, returns a 3-tuple containing two empty strings\n",
      " |      and the original string.\n",
      " |  \n",
      " |  rsplit(self, /, sep=None, maxsplit=-1)\n",
      " |      Return a list of the words in the string, using sep as the delimiter string.\n",
      " |      \n",
      " |        sep\n",
      " |          The delimiter according which to split the string.\n",
      " |          None (the default value) means split according to any whitespace,\n",
      " |          and discard empty strings from the result.\n",
      " |        maxsplit\n",
      " |          Maximum number of splits to do.\n",
      " |          -1 (the default value) means no limit.\n",
      " |      \n",
      " |      Splits are done starting at the end of the string and working to the front.\n",
      " |  \n",
      " |  rstrip(self, chars=None, /)\n",
      " |      Return a copy of the string with trailing whitespace removed.\n",
      " |      \n",
      " |      If chars is given and not None, remove characters in chars instead.\n",
      " |  \n",
      " |  split(self, /, sep=None, maxsplit=-1)\n",
      " |      Return a list of the words in the string, using sep as the delimiter string.\n",
      " |      \n",
      " |      sep\n",
      " |        The delimiter according which to split the string.\n",
      " |        None (the default value) means split according to any whitespace,\n",
      " |        and discard empty strings from the result.\n",
      " |      maxsplit\n",
      " |        Maximum number of splits to do.\n",
      " |        -1 (the default value) means no limit.\n",
      " |  \n",
      " |  splitlines(self, /, keepends=False)\n",
      " |      Return a list of the lines in the string, breaking at line boundaries.\n",
      " |      \n",
      " |      Line breaks are not included in the resulting list unless keepends is given and\n",
      " |      true.\n",
      " |  \n",
      " |  startswith(...)\n",
      " |      S.startswith(prefix[, start[, end]]) -> bool\n",
      " |      \n",
      " |      Return True if S starts with the specified prefix, False otherwise.\n",
      " |      With optional start, test S beginning at that position.\n",
      " |      With optional end, stop comparing S at that position.\n",
      " |      prefix can also be a tuple of strings to try.\n",
      " |  \n",
      " |  strip(self, chars=None, /)\n",
      " |      Return a copy of the string with leading and trailing whitespace remove.\n",
      " |      \n",
      " |      If chars is given and not None, remove characters in chars instead.\n",
      " |  \n",
      " |  swapcase(self, /)\n",
      " |      Convert uppercase characters to lowercase and lowercase characters to uppercase.\n",
      " |  \n",
      " |  title(self, /)\n",
      " |      Return a version of the string where each word is titlecased.\n",
      " |      \n",
      " |      More specifically, words start with uppercased characters and all remaining\n",
      " |      cased characters have lower case.\n",
      " |  \n",
      " |  translate(self, table, /)\n",
      " |      Replace each character in the string using the given translation table.\n",
      " |      \n",
      " |        table\n",
      " |          Translation table, which must be a mapping of Unicode ordinals to\n",
      " |          Unicode ordinals, strings, or None.\n",
      " |      \n",
      " |      The table must implement lookup/indexing via __getitem__, for instance a\n",
      " |      dictionary or list.  If this operation raises LookupError, the character is\n",
      " |      left untouched.  Characters mapped to None are deleted.\n",
      " |  \n",
      " |  upper(self, /)\n",
      " |      Return a copy of the string converted to uppercase.\n",
      " |  \n",
      " |  zfill(self, width, /)\n",
      " |      Pad a numeric string with zeros on the left, to fill a field of the given width.\n",
      " |      \n",
      " |      The string is never truncated.\n",
      " |  \n",
      " |  ----------------------------------------------------------------------\n",
      " |  Static methods defined here:\n",
      " |  \n",
      " |  __new__(*args, **kwargs) from builtins.type\n",
      " |      Create and return a new object.  See help(type) for accurate signature.\n",
      " |  \n",
      " |  maketrans(x, y=None, z=None, /)\n",
      " |      Return a translation table usable for str.translate().\n",
      " |      \n",
      " |      If there is only one argument, it must be a dictionary mapping Unicode\n",
      " |      ordinals (integers) or characters to Unicode ordinals, strings or None.\n",
      " |      Character keys will be then converted to ordinals.\n",
      " |      If there are two arguments, they must be strings of equal length, and\n",
      " |      in the resulting dictionary, each character in x will be mapped to the\n",
      " |      character at the same position in y. If there is a third argument, it\n",
      " |      must be a string, whose characters will be mapped to None in the result.\n",
      "\n",
      "None\n"
     ]
    }
   ],
   "source": [
    "# useful tips by using help()\n",
    "print(help(str))\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 3",
   "language": "python",
   "name": "python3"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.7.1"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 2
}