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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 alias(col, mapping):
 """ Returns a collection of dictionaries with the keys renamed according to the mapping [{'edition': 1, 'isbn': 1}, {'edition': 2, 'isbn': 2}] [{'b': 1}] """

    if not is_list(col):
        col = [col]

    def _block(dct):
        return rename(dct, mapping)

    return map(_block, col)