(self)
return NO(self._remove_brackets)
Returns a sum of NO objects that contain no ambiguous q-operators.

        If an index q has range both above and below fermi, the operator F(q)
        is ambiguous in the sense that it can be both a q-creator and a q-annihilator.
        If q is dummy, it is assumed to be a summation variable and this method
        rewrites it into a sum of NO terms with unambiguous operators:

        {Fd(p)*F(q)} = {Fd(a)*F(b)} + {Fd(a)*F(i)} + {Fd(j)*F(b)} -{F(i)*Fd(j)}

        where a,b are above and i,j are below fermi level.
Returns a sum of NO objects that contain no ambiguous q-operators.
Returns a sum of NO objects that contain no ambiguous q - operators .
def _expand_operators(self):
        """
        Returns a sum of NO objects that contain no ambiguous q-operators.

        If an index q has range both above and below fermi, the operator F(q)
        is ambiguous in the sense that it can be both a q-creator and a q-annihilator.
        If q is dummy, it is assumed to be a summation variable and this method
        rewrites it into a sum of NO terms with unambiguous operators:

        {Fd(p)*F(q)} = {Fd(a)*F(b)} + {Fd(a)*F(i)} + {Fd(j)*F(b)} -{F(i)*Fd(j)}

        where a,b are above and i,j are below fermi level.
        """
        return NO(self._remove_brackets)
def _expand_operators ( self ) : return NO ( self . _remove_brackets )