How to handle Error "'NoneType' object has no attribute 'keys'", when converting list to DataFrame

Question

Trying to create a dataframe from a list but get error "'NoneType' object has no attribute 'keys'"

import numpy as np
import pandas as pd
import requests
import json
from sklearn import preprocessing
from sklearn.preprocessing import OneHotEncoder

person = []
position = []
skaterstats = []
person = []
player_id = {}
 for game_id in range(2018020001, 2018020002, 1):
    url = 'https://statsapi.web.nhl.com/api/v1/game/{}/feed/live'.format(game_id)
    r = requests.get(url)
    game_data = r.json()

for homeaway in ['home','away']:
    player_dict = game_data.get('liveData').get('boxscore').get('teams').get(homeaway).get('skaters')
    player_id[homeaway] = player_dict

for homeaway in player_id:
    for playerID in player_id[homeaway]:
        play_dict_person = game_data.get('liveData').get('boxscore').get('teams').get(homeaway).get('players').get('ID' + str(playerID)).get('person')
        play_dict_position = game_data.get('liveData').get('boxscore').get('teams').get(homeaway).get('players').get('ID' + str(playerID)).get('position')
        play_dict_skaterstats = game_data.get('liveData').get('boxscore').get('teams').get(homeaway).get('players').get('ID' + str(playerID)).get('stats').get('skaterStats')
        person.append(play_dict_person)
        position.append(play_dict_position)
        skaterstats.append(play_dict_skaterstats)

df_person = pd.DataFrame(person).head()
df_position = pd.DataFrame(position).head()
df_skaterstats = pd.DataFrame(skaterstats).head()

----> 3 df_skaterstats = pd.DataFrame(skaterstats).head() 

AttributeError: 'NoneType' object has no attribute 'keys'

The error occurs occurs only on this DataFrame, I have checked that the path should be correct and all. Link to the API below if it would to any guidance.

This is the API: https://statsapi.web.nhl.com/api/v1/game/2017020002/feed/live

Answer 1

Some players have no statistics, so play_dict_skaterstats for them is None. You might need to replace

skaterstats.append(play_dict_skaterstats)

with

if play_dict_skaterstats: 
    skaterstats.append(play_dict_skaterstats)

to skip these cases

Or you might need to set default values for this case, e.g.

if not play_dict_skaterstats:
    play_dict_skaterstats = {}
    play_dict_skaterstats['timeOnIce'] = None
    play_dict_skaterstats['assists'] = None
    ...
skaterstats.append(play_dict_skaterstats)