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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 complete(self, GET):
 """ Complete the OAuth2 flow by fetching an access token with the provided code in the GET parameters. """

        if 'error' in GET:
            raise OAuthError(
                _("Received error while obtaining access token from %s: %s") % (
                    self.access_token_url, GET['error']))
        return self.get_access_token(code=GET.get('code'))