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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 deprecated (func):
 """A decorator which can be used to mark functions as deprecated. It emits a warning when the function is called."""

    def newfunc (*args, **kwargs):
        """Print deprecated warning and execute original function."""
        warnings.warn("Call to deprecated function %s." % func.__name__,
                      category=DeprecationWarning)
        return func(*args, **kwargs)
    return update_func_meta(newfunc, func)