try:

    import idlelib.PyShell

except ImportError:

    # IDLE is not installed, but maybe PyShell is on sys.path:

    try:

        import PyShell

    except ImportError:

        raise

    else:

        import os

        idledir = os.path.dirname(os.path.abspath(PyShell.__file__))

        if idledir != os.getcwd():

            # We're not in the IDLE directory, help the subprocess find run.py

            pypath = os.environ.get('PYTHONPATH', '')

            if pypath:

                os.environ['PYTHONPATH'] = pypath + ':' + idledir

            else:

                os.environ['PYTHONPATH'] = idledir

        PyShell.main()

else:

    idlelib.PyShell.main()