def fillna(arg, fill_value):
    return _ops.IfNull(arg, fill_value).to_expr()
If the user is not in the mapping provided to
dataset/ETHPy150Open cloudera/ibis/ibis/expr/api.py/fillna--crossover with--dataset/ETHPy150Open twisted/twisted/twisted/conch/test/test_checkers.py/InMemorySSHKeyDBTests.test_noKeysForUnauthorizedUser