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Thread 1 (Thread 2103):
#0  0x00007f17385a4a8d in pkgProblemResolver::MakeScores() ()
   from /usr/lib/libapt-pkg-libc6.10-6.so.4.8
No symbol table info available.
#1  0x00007f17385a5c4a in pkgProblemResolver::Resolve(bool) ()
   from /usr/lib/libapt-pkg-libc6.10-6.so.4.8
No symbol table info available.
#2  0x00007f17385a7c4a in pkgDistUpgrade(pkgDepCache&) ()
   from /usr/lib/libapt-pkg-libc6.10-6.so.4.8
No symbol table info available.
#3  0x00007f173882c728 in ?? ()
   from /usr/lib/python2.6/dist-packages/apt_pkg.so
No symbol table info available.
#4  0x00000000004a290d in PyEval_EvalFrameEx ()
No symbol table info available.
#5  0x00000000004a2e47 in PyEval_EvalFrameEx ()
No symbol table info available.
#6  0x00000000004a40e0 in PyEval_EvalCodeEx ()
No symbol table info available.
#7  0x00000000004a245f in PyEval_EvalFrameEx ()
No symbol table info available.
#8  0x00000000004a40e0 in PyEval_EvalCodeEx ()
No symbol table info available.
#9  0x00000000004a41b2 in PyEval_EvalCode ()
No symbol table info available.
#10 0x00000000004c33a0 in PyRun_FileExFlags ()
No symbol table info available.
#11 0x00000000004c3564 in PyRun_SimpleFileExFlags ()
No symbol table info available.
#12 0x0000000000418ab7 in Py_Main ()
No symbol table info available.
#13 0x00007f1738a5babd in __libc_start_main () from /lib/libc.so.6
No symbol table info available.
#14 0x0000000000417ca9 in _start ()
No symbol table info available.