Calibre crashed with TypeError: 'bool' object is not callable

Calibre crash with:

Traceback (most recent call last):
  File "/usr/bin/calibre", line 20, in <module>
    sys.exit(main())
  File "/usr/lib/calibre/calibre/gui2/main.py", line 438, in main
    communicate(opts, args)
  File "/usr/lib/calibre/calibre/gui2/main.py", line 384, in communicate
    t = build_pipe()
  File "/usr/lib/calibre/calibre/gui2/main.py", line 359, in build_pipe
    if iswindows():
TypeError: 'bool' object is not callable

--

Workaround:

Edit "/usr/lib/calibre/calibre/gui2/main.py", line 359

-if iswindows():
+if iswindows:

ProblemType: Crash
DistroRelease: Ubuntu 13.04
Package: calibre 0.9.18+dfsg-1
ProcVersionSignature: Ubuntu 3.8.0-12.21-generic 3.8.2
Uname: Linux 3.8.0-12-generic x86_64
ApportVersion: 2.9.1-0ubuntu1
Architecture: amd64
Date: Thu Mar 14 21:22:38 2013
EcryptfsInUse: Yes
ExecutablePath: /usr/bin/calibre
InterpreterPath: /usr/bin/python2.7
MarkForUpload: True
PackageArchitecture: all
ProcCmdline: /usr/bin/python2.7 /usr/bin/calibre
PythonArgs: ['/usr/bin/calibre']
SourcePackage: calibre
UpgradeStatus: Upgraded to raring on 2013-02-22 (20 days ago)
UserGroups: adm admin cdrom debian-tor dialout libvirtd lpadmin plugdev sambashare vboxusers