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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 drop_columns(records, slices):
 """ Drop all columns present in ``slices`` from records """

    for record in records:
        # Generate a set of indices to remove
        drop = set(i for slice in slices
                   for i in range(*slice.indices(len(record))))
        keep = [i not in drop for i in range(len(record))]
        record.seq = Seq(''.join(itertools.compress(record.seq, keep)), record.seq.alphabet)
        yield record