human
Here's a good function header given the following:
I wrote the below code

    inputs = tool.inputs
    input_json = {}
    inputs_dir = os.path.join(local_working_directory, '_inputs')
    def simple_value(input, param_dict_value, cwl_type=None):
        if (cwl_type is None):
            input_type = input.type
            cwl_type = GALAXY_TO_CWL_TYPES[input_type]
        if (cwl_type == 'null'):
            assert (param_dict_value is None)
            return None
        if (cwl_type == 'File'):
            dataset_wrapper = param_dict_value
            extra_files_path = dataset_wrapper.extra_files_path
            secondary_files_path = os.path.join(extra_files_path, '__secondary_files__')
            path = str(dataset_wrapper)
            if os.path.exists(secondary_files_path):
                safe_makedirs(inputs_dir)
                name = os.path.basename(path)
                new_input_path = os.path.join(inputs_dir, name)
                os.symlink(path, new_input_path)
                for secondary_file_name in os.listdir(secondary_files_path):
                    secondary_file_path = os.path.join(secondary_files_path, secondary_file_name)
                    os.symlink(secondary_file_path, (new_input_path + secondary_file_name))
                path = new_input_path
            return {'location': path, 'class': 'File'}
        elif (cwl_type == 'integer'):
            return int(str(param_dict_value))
        elif (cwl_type == 'long'):
            return int(str(param_dict_value))
        elif (cwl_type == 'float'):
            return float(str(param_dict_value))
        elif (cwl_type == 'double'):
            return float(str(param_dict_value))
        elif (cwl_type == 'boolean'):
            return string_as_bool(param_dict_value)
        elif (cwl_type == 'text'):
            return str(param_dict_value)
        elif (cwl_type == 'json'):
            raw_value = param_dict_value.value
            log.info(('raw_value    is    %s    (%s)' % (raw_value, type(raw_value))))
            return json.loads(raw_value)
        else:
            return...

What's a good function header?
assistant
#Here's a good function header.

def to_cwl_job(tool, param_dict, local_working_directory):