text: ############################################################################
  #  Licensed to the Apache Software Foundation (ASF) under one or more
  #  contributor license agreements.  See the NOTICE file distributed with
  #  this work for additional information regarding copyright ownership.
  #  The ASF licenses this file to You under the Apache License, Version 2.0
  #  (the "License"); you may not use this file except in compliance with
  #  the License.  You may obtain a copy of the License at
  #
  #      http://www.apache.org/licenses/LICENSE-2.0
  #
  #  Unless required by applicable law or agreed to in writing, software
  #  distributed under the License is distributed on an "AS IS" BASIS,
  #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  #  See the License for the specific language governing permissions and
  #  limitations under the License.
  
  from tajo_util import output_type
  from types import StringType
  
  @output_type('int4')
  def return_one():
      return 1
  
  @output_type("text")
  def helloworld():
      return 'Hello, World'
  
  # No decorator - blob
  def concat_py(str):
      return str+str
  
  @output_type('int4')
  def add_py(a,b):
      if a != None and b != None:
          return a+b
      else:
          return None
  
  def str_len(a):
      if a is None:
          return 0
      else:
          return len(a)