How Do I Reverse a Dictionary's Key-Value Pairs in Python?

Inverting a Dictionary Mapping

Often in programming, we encounter situations where we need to invert a dictionary, essentially flipping the keys and values to create a new dictionary. For instance, we might have a dictionary mapping keys to their corresponding values:

my_map = {'a': 1, 'b': 2}

And desire to create a new dictionary where the values become the keys and vice versa:

inv_map = {1: 'a', 2: 'b'}

To perform this operation in Python, we can utilize comprehension to create a new dictionary with the desired key-value pairs:

Python 3+:
inv_map = {v: k for k, v in my_map.items()}

Python 2:
inv_map = {v: k for k, v in my_map.iteritems()}

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