1.5.24 -2 cygwin python 2.5.1 problem, "import sqlite3" fail

[Vincent Huang]

when i try to import sqlite3 in python, it results:
        .......
        File "/usr/lib/python2.5/sqlite3/dbapi2.py"
            from _sqlite3 import *
       ImportError: No module name _sqlite3

   Actually, i can't find any modules named _sqlite3 in
/usr/lib/python2.5/.  How can i do? thanks
          "find /usr/lib/python2.5/  -print | grep _sqlite3"