code: def load_key(pubkey):
      
      try:
          return load_pem_public_key(pubkey.encode(), default_backend())
      except ValueError:
          # workaround for https://github.com/travis-ci/travis-api/issues/196
          pubkey = pubkey.replace('BEGIN RSA', 'BEGIN').replace('END RSA', 'END')
          return load_pem_public_key(pubkey.encode(), default_backend())
docs: Load public RSA key, with work-around for keys using
      incorrect header/footer format.
  
      Read more about RSA encryption with cryptography:
      https://cryptography.io/latest/hazmat/primitives/asymmetric/rsa/