import re
text = "Hello, world. I'm a boy, you're a girl."
replaced = re.sub(
'\S+', lambda m: re.match(r'^\W*(.*\w)\W*$', m.group()).group(1), text)
print(replaced)
aW1wb3J0IHJlCgp0ZXh0ID0gIkhlbGxvLCB3b3JsZC4gSSdtIGEgYm95LCB5b3UncmUgYSBnaXJsLiIKCnJlcGxhY2VkID0gcmUuc3ViKAogICAgJ1xTKycsIGxhbWJkYSBtOiByZS5tYXRjaChyJ15cVyooLipcdylcVyokJywgbS5ncm91cCgpKS5ncm91cCgxKSwgdGV4dCkKICAgIApwcmludChyZXBsYWNlZCkK