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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 _parse_plan(self, match):
 """Parse a matching plan line."""

        expected_tests = int(match.group("expected"))
        directive = Directive(match.group("directive"))

        # Only SKIP directives are allowed in the plan.
        if directive.text and not directive.skip:
            return Unknown()

        return Plan(expected_tests, directive)