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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 is_python3_identifier(possible_identifier):
 """ Returns `True` if the given `possible_identifier` can be used as an identifier in Python 3. """

    possible_identifier = unicodedata.normalize('NFKC', possible_identifier)
    return (
        bool(possible_identifier) and
        _is_in_id_start(possible_identifier[0]) and
        all(map(_is_in_id_continue, possible_identifier[1:]))
    ) and not iskeyword(possible_identifier)