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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 build_cards(jokers=False, num_jokers=0):
 """ Builds a list containing a full French deck of 52 Card instances. The cards are sorted according to ``DEFAULT_RANKS``. .. note: Adding jokers may break some functions & methods at the moment. :arg bool jokers: Whether or not to include jokers in the deck. :arg int num_jokers: The number of jokers to include. :returns: A list containing a full French deck of 52 Card instances. """

    new_deck = []

    if jokers:
        new_deck += [Card("Joker", None) for i in xrange(num_jokers)]

    new_deck += [Card(value, suit) for value in VALUES for suit in SUITS]

    return new_deck