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Dictionary:- Python dictionary is an unordered collection of items where each, item is a key:value pair. It is also refer to a dictionary as a mapping between a, set f keys/indices and a set of values., Important features of dictionaries: Each key maps to a value.,  Each key is separated from its values by a colon sign, the items are, separated by commas and the entire dictionary is enclosed in curly, braces.,  Keys are unique within a dictionary while values may not be.,  The value of dictionary can be of any type, but the keys must be of an, immutable data type such as strings, numbers or tuples.,  Dictionary is mutable. We can add new items or change the value of, existing items., Creating a Dictionary, Syntax:Dictionary name= {‘key1’:’value’, ‘key2’:’value’……… ‘keyn’:’valuen}, Methods to create dictionary:, 1. D1= { }, 2. D2= {key:value}, 3. D=dict(), Accessing elements in a dictionary:, To access dictionary elements you can use the familiar square brackets along, with the key to obtain its values:, Syntax:- print(dictionaryname=[‘key’]), Traversing a dictionary:, Traversing a dictionary means accessing each element of a dictionary. This can, be done by using for loop., Syntax:- for I in dictionary name:, Print(I, dictionaryname[I]), Do practice in rough copy:, 1. Create a dictionary of 5 key:value pair., 2. Access the two elements from a dictionary., 3. Traversing a dictionary.