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pythondictionarylist-comprehensiondictionary-comprehension

Create a dictionary with comprehension

Can I use list comprehension syntax to create a dictionary?

For example, by iterating over pairs of keys and values:

d = {... for k, v in zip(keys, values)}
Solution

  • Use a dict comprehension (Python 2.7 and later):

    {key: value for key, value in zip(keys, values)}

    Alternatively, use the dict constructor:

    pairs = [('a', 1), ('b', 2)]
dict(pairs)                          # → {'a': 1, 'b': 2}
dict((k, v + 10) for k, v in pairs)  # → {'a': 11, 'b': 12}

    Given separate lists of keys and values, use the dict constructor with zip:

    keys = ['a', 'b']
values = [1, 2]
dict(zip(keys, values))              # → {'a': 1, 'b': 2}