from __future__ import print_function
import __builtin__
oldprint = __builtin__.print
def myprint(*args, **kwargs):
oldprint('myprint', end='! ') # print to sys.stdout
oldprint(*args, **kwargs)
__builtin__.print = myprint # monkey-patch, henceforth `print` refers to `myprint`
print('abc')
# note: it won't help you against `sys.stdout.write()`, `os.write()`, modules that don't use `print_function`, etc
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