def METHOD_NAME(self):
    if not self.options.header_only:
        tc = CMakeToolchain(self)
        tc.cache_variables["FMT_DOC"] = False
        tc.cache_variables["FMT_TEST"] = False
        tc.cache_variables["FMT_INSTALL"] = True
        tc.cache_variables["FMT_LIB_DIR"] = "lib"
        if self._has_with_os_api_option:
            tc.cache_variables["FMT_OS"] = bool(self.options.with_os_api)
        tc.METHOD_NAME()