text: from trustar2.base import fluent, ParamsSerializer, Param
  
  
  @fluent
  class BaseHandler(object):
  
      def __init__(self, config=None):
          self.config = config
          self.payload_params = ParamsSerializer()
          self.query_params = ParamsSerializer()
  
  
      def set_payload_param(self, key, value):
          """Adds a new param to set of payload params."""
          param = Param(key=key, value=value)
          self.payload_params.add(param)
  
  
      def set_query_param(self, key, value):
          """Adds a new param to set of query params."""
          param = Param(key=key, value=value)
          self.query_params.add(param)
  
      def set_trustar_config(self, trustar_config):
          self.config = trustar_config
  
      def _argument_to_list(self, arg):
          iterables = (list, tuple, set)
          return arg if isinstance(arg, iterables) else [arg]
      
      def _argument_to_unique_list(self, arg):
          return list(set(self._argument_to_list(arg)))
  