docs: def ingest_environ(model_path=''):
  
      ''' a method to convert environment variables to a python dictionary
  
      :param model_path: [optional] string with path to jsonmodel of data to ingest
      :return: dictionary with environmental variables
  
      NOTE:   if a model is provided, then only those fields in the model will be
              added to the output and the value of any environment variable which
              matches the uppercase name of each field in the model will be added
              to the dictionary if its value is valid according to the model. if
              a value is not valid, the method will throw a InputValidationError
      '''
  
  # convert environment variables into json typed data
      from os import environ, path
      typed_dict = {}
      environ_variables = dict(environ)
      for key, value in environ_variables.items():
          if value.lower() == 'true':
              typed_dict[key] = True
          elif value.lower() == 'false':
              typed_dict[key] = False
          elif value.lower() == 'null':
              typed_dict[key] = None
          elif value.lower() == 'none':
              typed_dict[key] = None
          else:
              try:
                  try:
                      typed_dict[key] = int(value)
                  except:
                      typed_dict[key] = float(value)
              except:
                  typed_dict[key] = value
  
  # feed environment variables through model
      if model_path:
          if not path.exists(model_path):
              raise ValueError('%s is not a valid file path.' % model_path)
          model_dict = load_settings(model_path)
          from jsonmodel.validators import jsonModel
          model_object = jsonModel(model_dict)
          default_dict = model_object.ingest(**{})
          for key in default_dict.keys():
              if key.upper() in typed_dict:
                  valid_kwargs = {
                      'input_data': typed_dict[key.upper()],
                      'object_title': 'Environment variable %s' % key.upper(),
                      'path_to_root': '.%s' % key
                  }
                  default_dict[key] = model_object.validate(**valid_kwargs)
          return default_dict
  
      return typed_dict