I am trying to run gdb, but as soon as I hit enter I get this error

Traceback (most recent call last):

  File "/usr/lib/python2.7/site.py", line 562, in <module>

    main()

  File "/usr/lib/python2.7/site.py", line 544, in main

    known_paths = addusersitepackages(known_paths)

  File "/usr/lib/python2.7/site.py", line 271, in addusersitepackages

    user_site = getusersitepackages()

  File "/usr/lib/python2.7/site.py", line 246, in getusersitepackages

    user_base = getuserbase() # this will also set USER_BASE

  File "/usr/lib/python2.7/site.py", line 236, in getuserbase

    USER_BASE = get_config_var('userbase')

  File "/usr/lib/python2.7/sysconfig.py", line 577, in get_config_var

    return get_config_vars().get(name)

  File "/usr/lib/python2.7/sysconfig.py", line 476, in get_config_vars

    _init_posix(_CONFIG_VARS)

  File "/usr/lib/python2.7/sysconfig.py", line 337, in _init_posix

    makefile = _get_makefile_filename()

  File "/usr/lib/python2.7/sysconfig.py", line 331, in _get_makefile_filename

    return os.path.join(get_path('platstdlib').replace("/usr/local","/usr",1), "config" + (sys.pydebug and "_d" or ""), "Makefile")

AttributeError: 'module' object has no attribute 'pydebug'

am I missing some package? I have 12.04

Edit:

$ file /usr/bin/gdb

/usr/bin/gdb: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.24, BuildID[sha1]=0x8cd6c593fd6ffe6fd72266bf3d3407ea599b8143, stripped



$ dpkg -S /usr/bin/gdb

gdb: /usr/bin/gdb