code: def import_keypair(self, keypair_name, key_material):
          
          query = self.query_factory(
              action="ImportKeyPair", creds=self.creds, endpoint=self.endpoint,
              other_params={"KeyName": keypair_name,
                            "PublicKeyMaterial": b64encode(key_material)})
          d = query.submit()
          return d.addCallback(self.parser.import_keypair, key_material)
docs: Import an existing SSH key into EC2. It supports:
              * OpenSSH public key format (e.g., the format in
                ~/.ssh/authorized_keys)
              * Base64 encoded DER format
              * SSH public key file format as specified in RFC4716
  
          @param keypair_name: The name of the key to create.
          @param key_material: The material in one of the supported format.
  
          @return: A L{Deferred} firing with a L{model.Keypair} instance if
              successful.
  
          TODO: there is no corresponding method in the 2009-11-30 version
               of the ec2 wsdl. Delete this?