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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 calculate_affinity(user1, user2, round=False):
 # pragma: no cover """ Quick one-off affinity calculations. Creates an instance of the ``MALAffinity`` class with ``user1``, then calculates affinity with ``user2``. :param str user1: First user :param str user2: Second user :param round: Decimal places to round affinity values to. Specify ``False`` for no rounding :type round: int or False :return: (float affinity, int shared) :rtype: tuple """

    return MALAffinity(base_user=user1, round=round).calculate_affinity(user2)