docs: def parse(cls, query_str):
  		""" Parse string that represent query component from URI
  
  		:param query_str: string without '?'-sign
  		:return: WURIQuery
  		"""
  		parsed_query = parse_qs(query_str, keep_blank_values=True, strict_parsing=True)
  		result = cls()
  		for parameter_name in parsed_query.keys():
  			for parameter_value in parsed_query[parameter_name]:
  				result.add_parameter(
  					parameter_name,
  					parameter_value if len(parameter_value) > 0 else None
  				)
  		return result