I have a function that builds a list from a very large file. That list is used several times at various stages. Obviously, it only needs to runs once and running it more would waste time.
My question is how to have a function run once and return the list but when that function is called again it simply returns the list and doesn't run again.
I'd rather not just make the list a global variable. I know I could use a while loop to remember it as well but that just seems wasteful. I assume there is a more elegant way of accomplishing what I'm looking for.
Am I looking to use decorators or singletons (not sure if they are in python).
Example:
state_ab = ['OH', "test", 'CO']
def build_US_state_list():
state_dict = []
for state in pycountry.subdivisions:
if state.country_code == 'US':
state_dict.append({'name': state.name, 'code': state.code[3:]})
return state_dict
def get_US_state_list():
try:
return state_dict
except:
state_dict = build_US_state_list()
print('ran')
return state_dict
def identify_and_add_US_states():
states = get_US_state_list()
print(states)
for i in range(0, len(state_ab)):
for state in states:
if state_ab[i] == state["code"]:
return state["code"]
