@dispatch(notnull)
def _print_python(expr, leaves=None):
    child, scope = print_python(leaves, expr._child)
    return ('notnull(%s)' % child,
            toolz.merge(scope, dict(notnull=lambda x: x is not None)))
dataset/ETHPy150Open blaze/blaze/blaze/compute/pyfunc.py/_print_python/original