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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 ext(obj, ext_name, ext_args):
 """ Run an extension by its name. \b EXT_NAME: The name of the extension. EXT_ARGS: Arguments that are passed to the extension. """

    try:
        mod = import_module('lightflow_{}.__main__'.format(ext_name))
        mod.main(ext_args)
    except ImportError as err:
        click.echo(_style(obj['show_color'],
                          'An error occurred when trying to call the extension',
                          fg='red', bold=True))
        click.echo('{}'.format(err))