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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def freeze(obj):
    '''
    Freeze python types by turning them into immutable structures.
    '''
    if isinstance(obj, dict):
        return ImmutableDict(obj)
    if isinstance(obj, list):
        return ImmutableList(obj)
    if isinstance(obj, set):
        return ImmutableSet(obj)
    return obj