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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 info_authn(self):
 """Check to see if user if authenticated for info.json. Must have Authorization header with value that has the form "Bearer TOKEN", where TOKEN is an appropriate and valid access token. """

        authz_header = request.headers.get('Authorization', '[none]')
        if (not authz_header.startswith('Bearer ')):
            return False
        token = authz_header[7:]
        return self.access_token_valid(
            token, "info_authn: Authorization header")