human
Solve the following python programming problem given the following code:
def do_py(self, arg) : 
    '
        py <command>: Executes a Python command.
        py: Enters interactive Python mode.
        End with ``Ctrl-D`` (Unix) / ``Ctrl-Z`` (Windows), ``quit()``, \'`exit()``.
        Non-python commands can be issued with ``cmd("your command")``.
        Run python code from external files with ``run("filename.py")``
        ' 
    self.pystate ['self'] = self 
    arg = arg.parsed.raw [2 :].strip () 
    localvars = ((self.locals_in_py and self.pystate) or { 
        
}) 
    interp = InteractiveConsole (locals = localvars) 
    interp.runcode ('import sys, os;sys.path.insert(0, os.getcwd())') 
    if arg.strip () : 
        interp.runcode (arg) 
else : 
        def quit() : 
            raise EmbeddedConsoleExit 
def onecmd_plus_hooks(arg) : 
            return self.onecmd_plus_hooks ((arg + '
')) 
def run(arg) : 
            try : 
                file = open (arg) 
                interp.runcode (file.read ()) 
                file.close () 
except IOError as e : 
                self.perror (e) 
self.pystate ['quit'] = quit 
        self.pystate ['exit'] = quit 
        self.pystate ['cmd'] = onecmd_plus_hooks 
        self.pystate ['run'] = run 
        try : 
            cprt = 'Type "help", "copyright", "credits" or "license" for more information.' 
            keepstate = Statekeeper (sys, ('stdin', 'stdout')) 
            sys.stdout = self.stdout 
            sys.stdin = keepstate.stdin 
            interp.interact (banner = ('Python %s on %s
%s
(%s)
%s' % (sys.version, sys.platform, cprt, self.__class__.__name__, self.do_py.__doc__))) 
except EmbeddedConsoleExit : 
            pass 
keepstate.restore () 

    
    

    Fix the buggy line: sys.stdin = keepstate.stdin
assistant
#Here is Python code to fix the buggy line: sys.

sys.stdin = self.stdin