'Always create a quasi-particle?  (create hole or create particle)
>>> from sympy import Symbol
>>> from sympy.physics.secondquant import F
>>> a = Symbol(\'a\', above_fermi=True)
>>> i = Symbol(\'i\', below_fermi=True)
>>> p = Symbol(\'p\')
>>> F(a).is_only_q_creator
False
>>> F(i).is_only_q_creator
True
>>> F(p).is_only_q_creator
False'

@property
def is_only_q_creator(self):

    return self.is_only_below_fermi
