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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 maybe_show_progress(it, show_progress, **kwargs):
 """Optionally show a progress bar for the given iterator. Parameters it : iterable The underlying iterator. show_progress : bool Should progress be shown. **kwargs Forwarded to the click progress bar. Returns ------- itercontext : context manager A context manager whose enter is the actual iterator to use. Examples -------- .. code-block:: python with maybe_show_progress([1, 2, 3], True) as ns: for n in ns: """

    if show_progress:
        return click.progressbar(it, **kwargs)

    # context manager that just return `it` when we enter it
    return CallbackManager(lambda it=it: it)