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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 seq_sha1(seq, normalize=True):
 """returns unicode sha1 hexdigest for sequence `seq`. 'da39a3ee5e6b4b0d3255bfef95601890afd80709' '2108994e17f6cca9ff2352ada92b6511db076034' '2108994e17f6cca9ff2352ada92b6511db076034' '9482340281b5fc8f2a298dbbd6b82fe42159b6c5' """


    seq = normalize_sequence(seq) if normalize else seq
    bseq = seq.encode("ascii")
    return hashlib.sha1(bseq).hexdigest()