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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 get_backend_path(service):
 """Return the dotted path of the matching backend."""

    for backend in _get_backends():
        try:
            if backend.service_allowed(service):
                return "%s.%s" % (backend.__class__.__module__, backend.__class__.__name__)
        except AttributeError:
            raise NotImplementedError("%s.%s.service_allowed() not implemented" % (
                backend.__class__.__module__, backend.__class__.__name__)
            )
    return None