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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def interactive_shell():
 """ Coroutine that starts a Python REPL from which we can access the global counter variable. """

    print('You should be able to read and update the "counter[0]" variable from this shell.')
    try:
        yield from embed(globals=globals(), return_asyncio_coroutine=True, patch_stdout=True)
    except EOFError:
        # Stop the loop when quitting the repl. (Ctrl-D press.)
        loop.stop()