Python中如何移除字典列表里值为N/A的键

给定如下字典列表，需要移除所有值为"N/A"的键：

Data = [
  {
    "Area": "Los Angeles",
    "Idle": "N/A",
    "Downtime": "N/A",
    "Production": "N/A",
    "Total": "0.00 kWh",
    "Total_Cost": "$ 0.00",
    "Total_Idle_Cost": "N/A"
  },
  {
    "Area": "Oklohoma",
    "Idle": "N/A",
    "Downtime": "N/A",
    "Production": "N/A",
    "Total": "0.00 kWh",
    "Total_Cost": "$ 0.00",
    "Total_Idle_Cost": "N/A"
  }]

方法一：生成新的清理后列表（推荐） #

用列表推导式结合字典推导式，简洁高效地生成过滤后的新列表，不会修改原始数据：

cleaned_data = [{k: v for k, v in item.items() if v != "N/A"} for item in Data]

执行后，cleaned_data即为期望的结果：

[
  {
    "Area": "Los Angeles",
    "Total": "0.00 kWh",
    "Total_Cost": "$ 0.00"
  },
  {
    "Area": "Oklohoma",
    "Total": "0.00 kWh",
    "Total_Cost": "$ 0.00"
  }
]

方法二：原地修改原始列表 #

如果需要直接修改原始列表，可通过循环遍历每个字典，先收集要删除的键再批量删除（避免遍历字典时修改结构引发异常）：

for item in Data:
    keys_to_remove = [k for k, v in item.items() if v == "N/A"]
    for k in keys_to_remove:
        del item[k]

执行后，原始的Data变量就会变为清理后的状态。

内容的提问来源于stack exchange，提问作者Marc Jen Dynver Garcia