def add_preprocessor(preproc):
def decorator(func):<EOL><INDENT>func = ScriptAdaptor._wrap(func)<EOL>func._add_preprocessor(preproc)<EOL>return func<EOL><DEDENT>return decorator<EOL>
Define a preprocessor to run after the arguments are parsed and
before the function is executed, when running in console script
mode.

:param preproc: The callable, which will be passed the Namespace
                object generated by argparse.