def METHOD_NAME(self, msg: ForwardMsg) -> None:
    """Enqueue a ForwardMsg for this context's session."""
    if msg.HasField("page_config_changed") and not self._set_page_config_allowed:
        raise StreamlitAPIException(
            "`set_page_config()` can only be called once per app page, "
            + "and must be called as the first Streamlit command in your script.\n\n"
            + "For more information refer to the [docs]"
            + "(https://docs.streamlit.io/library/api-reference/utilities/st.set_page_config)."
        )
    # We want to disallow set_page config if one of the following occurs:
    # - set_page_config was called on this message
    # - The script has already started and a different st call occurs (a delta)
    if msg.HasField("page_config_changed") or (
        msg.HasField("delta") and self._has_script_started
    ):
        self._set_page_config_allowed = False
    # Pass the message up to our associated ScriptRunner.
    self._enqueue(msg)