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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 _convert_to_var(self, graph, var_res):
 """ Create tf.Variables from a list of numpy arrays var_res: dictionary of numpy arrays with the key names corresponding to var """

        with graph.as_default():
            var = {}
            for key, value in var_res.items():
                if value is not None:
                    var[key] = tf.Variable(value, name="tf_%s" % key)
                else:
                    var[key] = None
        return var