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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_user_details(self, response):
 """Return user details from OAuth Profile Google App Engine App"""

        email = response['email']
        username = response.get('nickname', email).split('@', 1)[0]
        return {'username': username,
                'email': email,
                'fullname': '',
                'first_name': '',
                'last_name': ''}