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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 rev_c(read):
 """ return reverse completment of read """

    rc = []
    rc_nucs = {'A':'T', 'T':'A', 'G':'C', 'C':'G', 'N':'N'}
    for base in read:
        rc.extend(rc_nucs[base.upper()])
    return rc[::-1]