human
Solve the following python programming problem given the following code:
def _create_mapping_fn(map_cmd) : 
    def _inner_map(keys, fn) : 
        global PROXY_INDEX 
        fn_proxy [PROXY_INDEX] = fn 
        vim.command (('%s %s :py venom.fn_proxy[%d]()<CR>' % (map_cmd, keys, PROXY_INDEX))) 
        PROXY_INDEX += 1 
return map_cmd 

    
    

    Fix the buggy line: return map_cmd
assistant
#Here is Python code to fix the buggy line: return map_cmd
.

return def _inner_map(