Missing Modules - PI

Hi there,
Can you tell me how I could install those missing modules form the Raspberry PI?
cv2 unittest
numpy
difflib
I tried to install some packages using the sudo apt-get commands without any luck.
Thanks a lot.
Can you tell me how I could install those missing modules form the Raspberry PI?
cv2 unittest
numpy
difflib
I tried to install some packages using the sudo apt-get commands without any luck.

Thanks a lot.