def get_func(func_name):
    """Helper to return a function object by name. func_name must identify a
    function in this module or the path to a function relative to the base
    'modeling' module.
    """
    if func_name == '':
        return None
    new_func_name = name_compat.get_new_name(func_name)
    if new_func_name != func_name:
        logger.warn(
            'Remapping old function name: {} -> {}'.
            format(func_name, new_func_name)
        )
        func_name = new_func_name
    try:
        parts = func_name.split('.')
        # Refers to a function in this module
        if len(parts) == 1:
            return globals()[parts[0]]
        # Otherwise, assume we're referencing a module under modeling
        module_name = 'detectron.modeling.' + '.'.join(parts[:-1])
        module = importlib.import_module(module_name)
        return getattr(module, parts[-1])
    except Exception:
        logger.error('Failed to find function: {}'.format(func_name))
        raise
Helper to return a function object by name. func_name must identify a
    function in this module or the path to a function relative to the base
    'modeling' module.
    
detectron/modeling/model_builder.py