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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(self, diff):
 """Check that the new file introduced is at the proper depth The proper depth is 2 (contrib/user_example/new_file.py) """

        relative_path = relative_to_contrib(diff, self.project)
        assert len(relative_path.parts) == 2