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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 callwith(context_manager):
 """ A decorator to wrap execution of function with a context manager. """

    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwds):
            with context_manager:
                return func(*args, **kwds)
        return wrapper
    return decorator