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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 reverseComplement(seq):
    '''
    Helper function for generating reverse-complements
    '''
    revComp = ''
    complement = {'A':'T', 'C':'G', 'G':'C', 'T':'A', 'N':'N', '$':'$'}
    for c in reversed(seq):
        revComp += complement[c]
    return revComp