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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 _strip_empty_keys(self, params):
 """Added because the Dropbox OAuth2 flow doesn't work when scope is passed in, which is empty. """

        keys = [k for k, v in params.items() if v == '']
        for key in keys:
            del params[key]