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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 include(self):
 """Return fields to include :return list: a list of include information """

        include_param = self.qs.get('include', [])

        if current_app.config.get('MAX_INCLUDE_DEPTH') is not None:
            for include_path in include_param:
                if len(include_path.split('.')) > current_app.config['MAX_INCLUDE_DEPTH']:
                    raise InvalidInclude("You can't use include through more than {} relationships"
                                         .format(current_app.config['MAX_INCLUDE_DEPTH']))

        return include_param.split(',') if include_param else []