def import_main(name):
    """Imports the module that is to be interpreted as the main module.

       experimental is often invoked with a script meant to be run as the
       main module its source is transformed.  The invocation will be

       python -m experimental [trans1, trans2, ...] main_script

       Python identifies experimental as the main script; we artificially
       change this so that "main_script" is properly identified as such.
    """
    global MAIN_MODULE_NAME
    MAIN_MODULE_NAME = name
    return __import__(name)
