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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 _build_rules(specs):
 """Adapts the list of anillo urlmapping specs into a list of werkzeug rules or rules subclasses. :param list specs: A list of anillo url mapping specs. :return: generator """

    for spec in specs:
        if "context" in spec:
            yield Context(spec["context"], list(_build_rules(spec.get("routes", []))))
        else:
            rulespec = spec.copy()
            match = rulespec.pop("match")
            name = rulespec.pop("name")
            yield Rule(match, endpoint=name, **rulespec)