code: def compute_transformed(context):
      
  
      key_composite = compute_key_composite(
          password=context._._.password,
          keyfile=context._._.keyfile
      )
      kdf_parameters = context._.header.value.dynamic_header.kdf_parameters.data.dict
  
      if context._._.transformed_key is not None:
          transformed_key = context._._.transformed_key
      elif kdf_parameters['$UUID'].value == kdf_uuids['argon2']:
          transformed_key = argon2.low_level.hash_secret_raw(
              secret=key_composite,
              salt=kdf_parameters['S'].value,
              hash_len=32,
              type=argon2.low_level.Type.D,
              time_cost=kdf_parameters['I'].value,
              memory_cost=kdf_parameters['M'].value // 1024,
              parallelism=kdf_parameters['P'].value,
              version=kdf_parameters['V'].value
          )
      elif kdf_parameters['$UUID'].value == kdf_uuids['aeskdf']:
          transformed_key = aes_kdf(
              kdf_parameters['S'].value,
              kdf_parameters['R'].value,
              key_composite
          )
      else:
          raise Exception('Unsupported key derivation method')
  
      return transformed_key
docs: Compute transformed key for opening database