在Python中，如果值是nan/null/empty，如何从字典的列表中删除key和value？

在迭代一个字典或列表的值时，你不应该修改它。创建一个新的地址列表，其中包含你需要的值，然后用它替换现有的列表。

address_dic = {
    "source_id": 4402350,
    "address": [
            "address_type": "Primary",
            "address_line_1": "11815",
            "address_line_2": float("nan")
            "address_type": "work",
            "address_line_1": float("nan"),
            "address_line_2": 123
new_address = []
for addr in address_dic["address"]:
    # iterate through the dictionary and add the key-value pair
    # into a new dictionary if the value is not nan
    new_addr = {key: val for key, val in addr.items() if val == val} 
    new_address.append(new_addr)
address_dic["address"] = new_address
Output
    "source_id": 4402350,
    "address": [
            "address_type": "Primary",
            "address_line_1": "11815",
            "address_type": "work",
            "address_line_2": 123
One-Liner
address_dic["address"] = [{key: val for key, val in addr.items() if val == val} for addr in address_dic["address"]]
你可以通过多种方式检查一个值是否是nan。
val = float("nan") # setting val as nan
import pandas as pd
pd.isna(val) # returns True if val is nan
Numpy
import numpy as np
np.isnan(val) # returns True if val is nan
没有外部图书馆
val == val # returns False if val is nan