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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 get_SHA1_bin(word):
 """ Return SHA1 hash of any string :param word: :return: """

    from hashlib import sha1
    if PY3 and isinstance(word, str):
        word = word.encode('utf-8')

    hash_s = sha1()
    hash_s.update(word)
    return bin(int(hash_s.hexdigest(), 16))[2:].zfill(160)