docs: def app_data(self, org_name, prod_name):
  
          ''' a method to retrieve the os appropriate path to user app data
  
          # https://www.chromium.org/user-experience/user-data-directory
  
          :param org_name: string with name of product/service creator
          :param prod_name: string with name of product/service
          :return: string with path to app data
          '''
  
          __name__ = '%s.app_data' % self.__class__.__name__
  
      # validate inputs
          org_name = self.fields.validate(org_name, '.org_name')
          prod_name = self.fields.validate(prod_name, '.prod_name')
  
      # construct empty fields
          data_path = ''
  
      # construct path from os
          if self.os.sysname == 'Windows':
              from re import compile
              xp_pattern = compile('^C:\\Documents and Settings')
              app_data = ''
              if os.environ.get('APPDATA'):
                  app_data = os.environ.get('APPDATA')
              if xp_pattern.findall(app_data):
                  data_path = '%s\\Local Settings\\Application Data\\%s\\%s' % (self.home, org_name, prod_name)
              else:
                  data_path = '%s\\AppData\\Local\\%s\\%s' % (self.home, org_name, prod_name)
  
          elif self.os.sysname == 'Darwin':
              data_path = '%s/Library/Application Support/%s/%s/' % (self.home, org_name, prod_name)
  
          elif self.os.sysname in ('Linux', 'FreeBSD', 'Solaris'):
              org_format = org_name.replace(' ','-').lower()
              prod_format = prod_name.replace(' ', '-').lower()
              data_path = '%s/.config/%s-%s/' % (self.home, org_format, prod_format)
  
          return data_path