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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 compute_positive_association(self, visible, hidden_probs, hidden_states):
 """Compute positive associations between visible and hidden units. :param visible: visible units :param hidden_probs: hidden units probabilities :param hidden_states: hidden units states :return: positive association = dot(visible.T, hidden) """

        if self.visible_unit_type == 'bin':
            positive = tf.matmul(tf.transpose(visible), hidden_states)

        elif self.visible_unit_type == 'gauss':
            positive = tf.matmul(tf.transpose(visible), hidden_probs)

        else:
            positive = None

        return positive