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Collection in python

There are basic two datatypes in python 


1. Immutable datatype : numeric , string , tuple

2. Mutable : list , dictionary , set


Immutable : Content cannot be changed or modified using the indexing operator ( assignment  statement )

Mutable : Content can be changed or modified using the indexing operator ( assignment  statement )


Numeric : int, float , complex numbers

Sequence : list, string, tuple, range

Mapping : dictionary

Set : set , frozenset

Boolean : is used for making more conditions for 'if' in True and False form



Collections in python :


1) Dictionary :

It is used to map arbitrary keys to value

Only immutable ( content can be changed ) objects can be used as keys to dictionaries

Ex :  D = { 'a' : 10 , 'b' : [20, 30] }   

           

2)  List :

It can collect multiple values, multiple types of objects and data collection in single variable. 

It is mutable. So operation such like remove, append , insert can be done here

Append : to add an item or whole list to the end of an existing list 

Extend : to add every items separated by commas to the end of an existing list (due to for loop working behind)

Indexing, slicing can be done here

Indexing : referring to an element position of an iterable within an ordered list

Slicing : is way of retrieving values from a list. use to modify or delete the items of mutable

Ex : L = [1 , 'a' , [ 2 , 'b' ] , ( 3, 4 )]


3)  Tuples  : 

It is immutable 

Ex : T = ( 1, 2, 3)   or   T =  1, 2, 3







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