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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 split(coll, factor):
 """Split a collection by using a factor :param coll: a collection :param factor: a collection of factors :returns: a dictionary {'classic': ['Debussy', 'Bach'], 'rock': ['Led Zeppelin', 'Metallica', 'Iron Maiden']} """

    groups = groupby(lambda x: x[0], itertools.izip(factor, coll))
    return dmap(lambda x: [y[1] for y in x], groups)