human
Solve the following python programming problem given the following code:
def _get_submatrix(self, slice0, slice1) : 
    'Return a submatrix of this matrix (new matrix is created).' 
    (slice0, slice1) = self._swap ((slice0, slice1)) 
    (shape0, shape1) = self._swap (self.shape) 
    def _process_slice(sl, num) : 
        if isinstance (sl, slice) : 
            (i0, i1) = (sl.start, sl.stop) 
            if (i0 is None) : 
                i0 = 0 
else : 
                if (i0 < 0) : 
                    i0 = (num + i0) 
if (i1 is None) : 
                i1 = num 
else : 
                if (i1 < 0) : 
                    i1 = (num + i1) 
return (i0, i1) 
else : 
            if np.isscalar (sl) : 
                if (sl < 0) : 
                    sl += num 
return (sl, (sl + 1)) 
else : 
                return (sl [0], sl [1]) 
def _in_bounds(i0, i1, num) : 
        if ((not (0 <= i0 < num)) or (not (0 < i1 <= num)) or (not (i0 < i1))) : 
            raise IndexError (('index out of bounds: 0<=%d<%d, 0<=%d<%d, %d<%d' % (i0, num, i1, num, i0, i1))) 
(i0, i1) = _process_slice (slice0, shape0) 
    (j0, j1) = _process_slice (slice1, shape1) 
    _in_bounds (i0, i1, shape0) 
    _in_bounds (j0, j1, shape1) 
    aux = _sparsetools.get_csr_submatrix (shape0, shape1, self.indptr, self.indices, self.data, i0, i1, self, j1) 
    (data, indices, indptr) = (aux [2], aux [1], aux [0]) 
    shape = self._swap (((i1 - i0), (j1 - j0))) 
    return self.__class__ ((data, indices, indptr), shape = shape) 

    
    

    Fix the buggy line: aux = _sparsetools.get_csr_submatrix (shape0, shape1, self.indptr, self.indices, self.data, i0, i1, self, j1)
assistant
#Here is Python program to fix the buggy line: aux = _sparsetools.

aux = _sparsetools.get_csr_submatrix (shape0, shape1, self.indptr, self.indices, self.data, i0, i1, j0, j1)