def access_token(self) -> AccessToken:
        """
        Returns an access token created from this refresh token.  Copies all
        claims present in this refresh token to the new access token except
        those claims listed in the `no_copy_claims` attribute.
        """
        access = self.access_token_class()

        # Use instantiation time of refresh token as relative timestamp for
        # access token "exp" claim.  This ensures that both a refresh and
        # access token expire relative to the same time if they are created as
        # a pair.
        access.set_exp(from_time=self.current_time)

        no_copy = self.no_copy_claims
        for claim, value in self.payload.items():
            if claim in no_copy:
                continue
            access[claim] = value

        return access

        Returns an access token created from this refresh token.  Copies all
        claims present in this refresh token to the new access token except
        those claims listed in the `no_copy_claims` attribute.
        
rest_framework_simplejwt/tokens.py