'Create new instance of own class with args exactly as provided by
caller but returning the self class identity if args is empty.
This is handy when we want to optimize things, e.g.
>>> from sympy import Mul, S
>>> from sympy.abc import x, y
>>> e = Mul(3, x, y)
>>> e.args
(3, x, y)
>>> Mul(*e.args[1:])
x*y
>>> e._new_rawargs(*e.args[1:])  # the same as above, but faster
x*y
Note: use this with caution. There is no checking of arguments at
all. This is best used when you are rebuilding an Add or Mul after
simply removing one or more terms. If modification which result,
for example, in extra 1s being inserted (as when collecting an
expression\'s numerators and denominators) they will not show up in
the result but a Mul will be returned nonetheless:
>>> m = (x*y)._new_rawargs(S.One, x); m
x
>>> m == x
False
>>> m.is_Mul
True
Another issue to be aware of is that the commutativity of the result
is based on the commutativity of self. If you are rebuilding the
terms that came from a commutative object then there will be no
problem, but if self was non-commutative then what you are
rebuilding may now be commutative.
Although this routine tries to do as little as possible with the
input, getting the commutativity right is important, so this level
of safety is enforced: commutativity will always be recomputed if
self is non-commutative and kwarg `reeval=False` has not been
passed.'

def _new_rawargs(self, *args, **kwargs):

    if (kwargs.pop('reeval', True) and (self.is_commutative is False)):
        is_commutative = None
    else:
        is_commutative = self.is_commutative
    return self._from_args(args, is_commutative)
