'True if Delta can be non-zero above fermi
Examples
>>> from sympy.functions.special.tensor_functions import KroneckerDelta
>>> from sympy import Symbol
>>> a = Symbol(\'a\', above_fermi=True)
>>> i = Symbol(\'i\', below_fermi=True)
>>> p = Symbol(\'p\')
>>> q = Symbol(\'q\')
>>> KroneckerDelta(p, a).is_above_fermi
True
>>> KroneckerDelta(p, i).is_above_fermi
False
>>> KroneckerDelta(p, q).is_above_fermi
True
See Also
is_below_fermi, is_only_below_fermi, is_only_above_fermi'

@property
def is_above_fermi(self):

    if self.args[0].assumptions0.get('below_fermi'):
        return False
    if self.args[1].assumptions0.get('below_fermi'):
        return False
    return True
