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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 openid_authorization_validator(self, request):
 """Additional validation when following the implicit flow. """

        request_info = super(ImplicitGrant, self).openid_authorization_validator(request)
        if not request_info:  # returns immediately if OAuth2.0
            return request_info

        # REQUIRED. String value used to associate a Client session with an ID
        # Token, and to mitigate replay attacks. The value is passed through
        # unmodified from the Authentication Request to the ID Token.
        # Sufficient entropy MUST be present in the nonce values used to
        # prevent attackers from guessing values. For implementation notes, see
        # Section 15.5.2.
        if not request.nonce:
            raise InvalidRequestError(
                request=request,
                description='Request is missing mandatory nonce parameter.'
            )
        return request_info