Don't use "hello %1".arg("world") : arg() can't be used in Python 3 about pybitmessage HOT 6 OPEN

$ cat qt4translate.py 
from PyQt4 import QtGui
print(QtGui.QApplication.translate("default", "hello %1").arg("world"))

$ python2 qt4translate.py 
hello world

$ cat qt5translate.py 
from PyQt5 import QtWidgets
print(QtWidgets.QApplication.translate("default", "hello %1").arg("world"))

$ python2 qt5translate.py 
Traceback (most recent call last):
  File "qt5translate.py", line 2, in <module>
    print(QtWidgets.QApplication.translate("default", "hello %1").arg("world"))
AttributeError: 'unicode' object has no attribute 'arg'

$ cat qtpytranslate.py 
from qtpy import QtWidgets
print(QtWidgets.QApplication.translate("default", "hello %1").arg("world"))

$ python2 qtpytranslate.py 
Traceback (most recent call last):
  File "qtpytranslate.py", line 2, in <module>
    print(QtWidgets.QApplication.translate("default", "hello %1").arg("world"))
AttributeError: 'unicode' object has no attribute 'arg'

$ cat qt5translate-format.py 
from PyQt5 import QtWidgets
print(QtWidgets.QApplication.translate("default", "hello {0}").format("world"))

$ python2 qt5translate-format.py 
hello world

$ cat qt4translate-format.py 
from PyQt4 import QtGui
print(QtGui.QApplication.translate("default", "hello {0}").format("world"))

$ python2 qt4translate-format.py 
Traceback (most recent call last):
  File "qt4translate-format.py", line 2, in <module>
    print(QtGui.QApplication.translate("default", "hello {0}").format("world"))
AttributeError: 'QString' object has no attribute 'format'

$ cat qt5translate-format-str.py
from PyQt5 import QtWidgets
print(str(QtWidgets.QApplication.translate("default", "hello {0}")).format("world"))

$ python2 qt5translate-format-str.py
hello world

$ cat qt4translate-format-str.py 
from PyQt4 import QtGui
print(str(QtGui.QApplication.translate("default", "hello {0}")).format("world"))

$ python2 qt4translate-format-str.py 
hello world

$ python3 qt5translate-format-str.py
hello world

$ python3 qt4translate-format-str.py
hello world