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pythontypesimmutabilitymutable

Chart of mutable versus immutable types

Is there a table or a chart somewhere online which shows what types (inbuilt) are mutable and immutable in python?

Solution

  • I am not sure of a chart, but basically:

    Mutable:

    list, dictionary, bytearray Note: bytearray is not a sequence though.

    Immutable:

    tuple, str

    You can check for mutability with:

    >>> import collections
>>> l = range(10)
>>> s = "Hello World"
>>> isinstance(l, collections.MutableSequence)
True
>>> isinstance(s, collections.MutableSequence)
False

    For a dictionary (mapping):

    >>> isinstance({}, collections.MutableMapping)
True