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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 _recurse(self, matrix, m_list, indices, output_m_list=[]):
 """ This method recursively finds the minimal permutations using a binary tree search strategy. Args: matrix: The current matrix (with some permutations already performed). m_list: The list of permutations still to be performed indices: Set of indices which haven't had a permutation performed on them. """

        # check to see if we've found all the solutions that we need
        if self._finished:
            return

        # if we're done with the current manipulation, pop it off.
        while m_list[-1][1] == 0:
            m_list = copy(m_list)
            m_list.pop()
            # if there are no more manipulations left to do check the value
            if not m_list:
                matrix_sum = np.sum(matrix)
                if matrix_sum < self._current_minimum:
                    self.add_m_list(matrix_sum, output_m_list)
                return

        # if we wont have enough indices left, return
        if m_list[-1][1] > len(indices.intersection(m_list[-1][2])):
            return

        if len(m_list) == 1 or m_list[-1][1] > 1:
            if self.best_case(matrix, m_list, indices) > self._current_minimum:
                return

        index = self.get_next_index(matrix, m_list[-1], indices)

        m_list[-1][2].remove(index)

        # Make the matrix and new m_list where we do the manipulation to the
        # index that we just got
        matrix2 = np.copy(matrix)
        m_list2 = deepcopy(m_list)
        output_m_list2 = copy(output_m_list)

        matrix2[index, :] *= m_list[-1][0]
        matrix2[:, index] *= m_list[-1][0]
        output_m_list2.append([index, m_list[-1][3]])
        indices2 = copy(indices)
        indices2.remove(index)
        m_list2[-1][1] -= 1

        # recurse through both the modified and unmodified matrices

        self._recurse(matrix2, m_list2, indices2, output_m_list2)
        self._recurse(matrix, m_list, indices, output_m_list)