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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 max_element (elements, ordered = None):
 """ Returns the maximum number in 'elements'. Uses 'ordered' for comparisons, or '<' is none is provided. """

    assert is_iterable(elements)
    assert callable(ordered) or ordered is None
    if not ordered: ordered = operator.lt

    max = elements [0]
    for e in elements [1:]:
        if ordered (max, e):
            max = e

    return max