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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 get_function_doc(function, config=default_config):
 """Return doc for a function."""

    if config.exclude_function:
        for ex in config.exclude_function:
            if ex.match(function.__name__):
                return None

    return _doc_object(function, 'function', config=config)