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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 open_submission_page(self, url=None, submission=None):
 """ Open an instance of the submission page for the given submission URL. """

        from .submission_page import SubmissionPage

        with self.term.loader('Loading submission'):
            page = SubmissionPage(self.reddit, self.term, self.config,
                                  self.oauth, url=url, submission=submission)
        if not self.term.loader.exception:
            return page