dictionary - Confused about python syntax -

i have looked on web , have not been able find answer question. trying understand python code , came across class declaration looks this:

s_list = []     last_name = ""  def __init__(self, last_name, curr_date, difference):     self.last_name = last_name     self.s_list = {curr_date:difference}     self.d_list = []     self.d_list.append(curr_date) 

what happening inside curly braces? initializing dictionary? later in main file used this:

n = n_dict[last_name] n.d_list.append(curr_date) n.s_list[curr_date] = difference 

where n temporary dictionary used add onto n_dict, n_dict being dictionary contains information class.

why {:} notation used? there other way have been done?

any answers appreciated!

{curr_date:difference} created anonymous dictionary.instead, can create dictionary name :

dict_name={} dict_name[curr_date]= difference self.s_list=dict_name 

also, can create dictionary using dict(): self.s_list=dict(curr_date=difference)

there other ways create dictionary in python!