<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def list_users(ctx, search, uuid, active):
 """List all locally known users"""


    users = ctx.obj['db'].objectmodels['user']

    for found_user in users.find():
        if not search or (search and search in found_user.name):
            # TODO: Not 2.x compatible
            print(found_user.name, end=' ' if active or uuid else '\n')
            if uuid:
                print(found_user.uuid, end=' ' if active else '\n')
            if active:
                print(found_user.active)

    log("Done")