def METHOD_NAME(self, validated_data):
    """Force the Markdown document field to the Markdown document of the JWT Token if any.
    Parameters
    ----------
    validated_data : dictionary
        Deserialized values of each field after validation.
    Returns
    -------
    dictionary
        The "validated_data" dictionary is returned after modification.
    """
    markdown_document_id = self.context["view"].get_related_markdown_document_id()
    if not validated_data.get("markdown_document_id"):
        validated_data["markdown_document_id"] = markdown_document_id
    return super().METHOD_NAME(validated_data)