Example for default dict to handle missing keys.

example_default_dict.py

from collections import defaultdict
import numpy as np


def api_call(response_ok=True):
    if response_ok:
        return {'Released': 2010, 'Ratings': [{'Value': 98}]}
    else:
        return defaultdict(lambda: np.nan)
    

# Pretend to have bad API response
extra_info_ok = api_call(True)
extra_info_not_ok = api_call(False)


print(extra_info_ok['Released'])                   # Output: 2010
print(extra_info_not_ok['Released'])               # Output: np.nan

print(extra_info_ok['Ratings'][0]['Value'])        # Output: 98
print(extra_info_not_ok['Ratings'][0]['Value'])    # Output: TypeError