You can also find all animation curve nodes and delete them. Animation curve node type can be either of the followings: animCurveTL time distance animCurveTA time angle animCurveTT time time animCurveTU time double

you can use the following(not tested)

$sel = `ls -typ "animCruveTL"`;
for($i=0; $i<size($sel); $i++){
    delete $sel[$i];
}

By: Maulik Kataria [ Editor ]