def METHOD_NAME(self, xform):
    version_from_mapping = None
    if xform.build_id:
        version_from_mapping = self.version_mapping.get(xform.build_id, None)
        if not version_from_mapping:
            try:
                get_app_version = get_app(self.domain, xform.build_id).version
            except Http404:
                get_app_version = None
            if get_app_version:
                version_from_mapping = int(get_app_version)
            self.version_mapping[xform.build_id] = version_from_mapping
    return version_from_mapping