Amazon How to describe and cancel conversion tasks

1)
Export Aws Access and Secret keys
#export AWS_ACCESS_KEY=XXXXXXXXXXXXXXXXXXXXX
#export AWS_SECRET_KEY=XXXXXXXXXXXXXXXXXXXXX

2) 
Create Import instance task

#ec2-import-instance win2k-r2-disk1.vmdk -f VMDK -t m1.small -a x86_64 -b import-export -o $AWS_ACCESS_KEY -w $AWS_SECRET_KEY --region us-west-1

3)
Describe Tasks

#ec2-describe-conversion-tasks -O $AWS_ACCESS_KEY -W $AWS_SECRET_KEY --region us-west-1

4)
Cancel Task

#ec2-cancel-conversion-task import-i-fh8kw7k3 -O $AWS_ACCESS_KEY -W $AWS_SECRET_KEY --region us-west-1