(self)
return 0
Can we destroy a quasi-particle?  (annihilate hole or annihilate particle)
        If so, would that be above or below the fermi surface?

        >>> from sympy import Symbol
        >>> from sympy.physics.secondquant import Fd
        >>> a = Symbol('a', above_fermi=1)
        >>> i = Symbol('i', below_fermi=1)
        >>> p = Symbol('p')

        >>> Fd(a).is_q_annihilator
        0
        >>> Fd(i).is_q_annihilator
        -1
        >>> Fd(p).is_q_annihilator
        -1
Can we destroy a quasi-particle?  (annihilate hole or annihilate particle)
        If so, would that be above or below the fermi surface?
Can we destroy a quasi - particle? ( annihilate hole or annihilate particle ) If so would that be above or below the fermi surface?
def is_q_annihilator(self):
        """
        Can we destroy a quasi-particle?  (annihilate hole or annihilate particle)
        If so, would that be above or below the fermi surface?

        >>> from sympy import Symbol
        >>> from sympy.physics.secondquant import Fd
        >>> a = Symbol('a', above_fermi=1)
        >>> i = Symbol('i', below_fermi=1)
        >>> p = Symbol('p')

        >>> Fd(a).is_q_annihilator
        0
        >>> Fd(i).is_q_annihilator
        -1
        >>> Fd(p).is_q_annihilator
        -1

        """
        if self.is_below_fermi:
            return -1
        return 0
def is_q_annihilator ( self ) : if self . is_below_fermi : return - 1 return 0