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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 build_calmjs_artifacts(dist, key, value, cmdclass=BuildCommand):
 """ Trigger the artifact build process through the setuptools. """


    if value is not True:
        return

    build_cmd = dist.get_command_obj('build')
    if not isinstance(build_cmd, cmdclass):
        logger.error(
            "'build' command in Distribution is not an instance of "
            "'%s:%s' (got %r instead)",
            cmdclass.__module__, cmdclass.__name__, build_cmd)
        return

    build_cmd.sub_commands.append((key, has_calmjs_artifact_declarations))