best and convenient way to upgrade the django project from older version to latest version -

best and convenient way to upgrade the django project from older version to latest version -

i want upgrade django project django 1.3 django 1.5. how can that.

right facing lots of problem solve this. , don't want utilize virtual environment old version. because on server causing lots of trouble. can provide me step step process same.

error getting:

502 bad gateway nginx/1.4.4

django