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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def export_vms( self, vms_names=None, standalone=False, export_dir='.', compress=False, init_file_name='LagoInitFile', out_format=YAMLOutFormatPlugin(), collect_only=False, with_threads=True, ):
 """ Export vm images disks and init file. The exported images and init file can be used to recreate the environment. Args: vms_names(list of str):
 Names of the vms to export, if None export all the vms in the env (default=None) standalone(bool):
 If false, export a layered image (default=False) export_dir(str):
 Dir to place the exported images and init file compress(bool):
 If True compress the images with xz (default=False) init_file_name(str):
 The name of the exported init file (default='LagoInitfile') out_format(:class:`lago.plugins.output.OutFormatPlugin`):
 The type of the exported init file (the default is yaml) collect_only(bool):
 If True, return only a mapping from vm name to the disks that will be exported. (default=False) with_threads(bool):
 If True, run the export in parallel (default=True) Returns Unless collect_only == True, a mapping between vms' disks. """

        return self.virt_env.export_vms(
            vms_names, standalone, export_dir, compress, init_file_name,
            out_format, collect_only, with_threads
        )