How can I get the .fbx source file path from a static mesh asset using python editor scripting?

    folder_path  = 'D:'
    now_selects = unreal.EditorUtilityLibrary.get_selected_assets()

    for now_asset in now_selects:
        #Get file name
        asset_name = now_asset.get_name()
        print('asset_name = {0}'.format(asset_name))

        #Get asset's import data
        import_data = now_asset.get_editor_property("asset_import_data")

        #Get asset's original source file path
        source_files = import_data.extract_filenames()
        print('source_files = {0}'.format(source_files))

        #Set source file path
        new_source_file = folder_path + '/' + asset_name + '.png' #Combine as you wish
        source_files = import_data.scripted_add_filename(new_source_file,0,'')