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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 finger(match, hash_type=None):
    '''
    Return the matching key fingerprints. Returns a dictionary.

    match
        The key for with to retrieve the fingerprint.

    hash_type
        The hash algorithm used to calculate the fingerprint

    .. code-block:: python

        >>> wheel.cmd('key.finger', ['minion1'])
        {'minions': {'minion1': '5d:f6:79:43:5e:d4:42:3f:57:b8:45:a8:7e:a4:6e:ca'}}

    '''
    if hash_type is None:
        hash_type = __opts__['hash_type']

    skey = get_key(__opts__)
    return skey.finger(match, hash_type)