Use new() instead of Image()._new()

[radarhere]

Pillow/src/PIL/Image.py

Line 983 in 4ecf1df

trns_im = Image()._new(core.new(self.mode, (1, 1)))

can be replaced with

trns_im = new(self.mode, (1, 1))

because that is what new() would do in this case.

This requires variables called new to be renamed in the surrounding code to avoid overlap, but that sounds like a good idea anyway.