parameters = pd.read_csv(params_filename, sep="\t")
free_parameters = parameters.columns.get_values().to_list()
free_parameters = [x for x in free_parameters if not x.startswith("fixed_") and x != "filename"]
for free_param in free_parameters:
free_param_range = np.unique(parameters[free_param])
ranges[free_param] = free_param_range
This worked perfectly fine in python 2 but not working for python 3. The error is shown in second line