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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_current_user(self):
 """ Returns the access key id used in this request as the current user id """

        if 'Authorization' in self.headers:
            match = self.access_key_regex.search(self.headers['Authorization'])
            if match:
                return match.group(1)

        if self.querystring.get('AWSAccessKeyId'):
            return self.querystring.get('AWSAccessKeyId')
        else:
            # Should we raise an unauthorized exception instead?
            return '111122223333'