old_contents: # -*- coding: utf-8 -*-
  
  # Copyright 2015 Spanish National Research Council
  # Copyright 2015 LIP - INDIGO-DataCloud
  #
  # Licensed 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.
  
  import six
  import six.moves.urllib.parse as urlparse
  
  
  def utf8(value):
      """Try to turn a string into utf-8 if possible.
  
      Code is modified from the utf8 function in
      http://github.com/facebook/tornado/blob/master/tornado/escape.py
  
      """
      if isinstance(value, six.text_type):
          return value.encode('utf-8')
      assert isinstance(value, str)
      return value
  
  
  def join_url(base, parts):
      """Join several parts into a url.
  
      :param base: the base url
      :parts: parts to join into the url
      """
      url = base
      if not isinstance(parts, (list, tuple)):
          parts = [parts]
  
      for p in parts:
          if p.startswith("/"):
              # We won't get an absolute url
              p = p[1:]
          url = urlparse.urljoin(url, p)
      return url
  
  
  def make_body(resource, parameters):
      """Creates body request using the parameters.
  
      :param resource: kind of resource
      :param parameters: list of parameters
      """
      content = {}
      for key in parameters.keys():
          content[key] = parameters[key]
      if resource:
          body = {resource: content}
      else:
          body = content
      return body
  
  
  def get_query_string(parameters):
      """Creates query string.
  
      :param parameters: list of parameters
      """
      if parameters is None:
          query_string = None
      else:
          query_string = urlparse.urlencode(parameters)
      return query_string
  
  
  def translate_parameters(translation, parameters):
      """Translates parameter names to OS
  
      :param translation: list of names for translation
      :param parameters: list of parameters
      """
      if not parameters:
          return None
      out = {}
      for key in parameters.keys():
          if key in translation:
              if parameters[key]:
                  out[translation[key]] = parameters[key]
      return out
  
new_contents: # -*- coding: utf-8 -*-
  
  # Copyright 2015 Spanish National Research Council
  # Copyright 2015 LIP - INDIGO-DataCloud
  #
  # Licensed 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.
  
  import six
  import six.moves.urllib.parse as urlparse
  
  
  def utf8(value):
      """Try to turn a string into utf-8 if possible.
  
      The original code was copied from the utf8 function in
      http://github.com/facebook/tornado/blob/master/tornado/escape.py
  
      """
      if value is None or isinstance(value, six.binary_type):
          return value
  
      if not isinstance(value, six.text_type):
          value = six.text_type(value)
  
      return value.encode('utf-8')
  
  
  def join_url(base, parts):
      """Join several parts into a url.
  
      :param base: the base url
      :parts: parts to join into the url
      """
      url = base
      if not isinstance(parts, (list, tuple)):
          parts = [parts]
  
      for p in parts:
          if p.startswith("/"):
              # We won't get an absolute url
              p = p[1:]
          url = urlparse.urljoin(url, p)
      return url
  
  
  def make_body(resource, parameters):
      """Creates body request using the parameters.
  
      :param resource: kind of resource
      :param parameters: list of parameters
      """
      content = {}
      for key in parameters.keys():
          content[key] = parameters[key]
      if resource:
          body = {resource: content}
      else:
          body = content
      return body
  
  
  def get_query_string(parameters):
      """Creates query string.
  
      :param parameters: list of parameters
      """
      if parameters is None:
          query_string = None
      else:
          query_string = urlparse.urlencode(parameters)
      return query_string
  
  
  def translate_parameters(translation, parameters):
      """Translates parameter names to OS
  
      :param translation: list of names for translation
      :param parameters: list of parameters
      """
      if not parameters:
          return None
      out = {}
      for key in parameters.keys():
          if key in translation:
              if parameters[key]:
                  out[translation[key]] = parameters[key]
      return out
  
subject: remove use of assert