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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 hash(mapping, bind, values):
 """ Generate a sha1 for each of the given values. """

    for v in values:
        if v is None:
            continue
        if not isinstance(v, six.string_types):
            v = six.text_type(v)
        yield sha1(v.encode('utf-8')).hexdigest()