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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 _safe_match_string(value):
 """Sanitize and represent a string argument in MATCH."""

    if not isinstance(value, six.string_types):
        if isinstance(value, bytes):  # should only happen in py3
            value = value.decode('utf-8')
        else:
            raise GraphQLInvalidArgumentError(u'Attempting to convert a non-string into a string: '
                                              u'{}'.format(value))

    # Using JSON encoding means that all unicode literals and special chars
    # (e.g. newlines and backslashes) are replaced by appropriate escape sequences.
    # JSON has the same escaping rules as MATCH / SQL, so no further escaping is necessary.
    return json.dumps(value)