pip install Crypto

$ python cryRSA.py

usage: cryRSA.py [-h] [-d] [-e] [-i INPUT] [-k KEY] [-o OUTPUT]
                 [-p PASSPHRASE] [-g GENERATE] [-V]

$ python cryRSA.py -g 4096
  Passphrase:
  Re-enter passphrase:

  Key can encrypt: True
  key can sygn: True
  key has private: True

  Public key created: public_key.pem
  Private key created: private_key.pem

$ python crysher.py -e -k public_key.pem -i my_file -o encrypt_file
  Passphrase:
  Re-enter passphrase:

$ python cryRSA.py -e -k public_key.pem -o encrypt_file  -p "my_password"
  hello, it's a secret message!

$ python crysher.py -d -key private_key.pem -i encrypt_file -o my_new_file