(self, i_j)
return self._array[i][j]
Returns the element located at in the i-th line and j-th
        column.
Returns the element located at in the i-th line and j-th
        column.
Returns the element located at in the i - th line and j - th column .
def __getitem__(self, i_j):
        """
        Returns the element located at in the i-th line and j-th
        column.
        """
        i, j = i_j
        return self._array[i][j]
def __getitem__ ( self , i_j ) : i , j = i_j return self . _array [ i ] [ j ]