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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 check_py(self, version, name, original, loc, tokens):
 """Check for Python-version-specific syntax."""

        internal_assert(len(tokens) == 1, "invalid " + name + " tokens", tokens)
        if self.target_info < get_target_info(version):
            raise self.make_err(CoconutTargetError, "found Python " + ".".join(version) + " " + name, original, loc, target=version)
        else:
            return tokens[0]