编写多个字典介绍csv文件

Question

我有一个文本文件，其中包含数千行，并且每行有关年龄的数据都存储在[x：y]位置。我想抓住它，并将其写入具有不同列年龄组的csv文件中。例如（年龄<50），（50 <年龄<80）等。这是我为此编写的代码。

 age_50 = {}
  age50_80 = {}
  age_80 = {}
  age = int(line[x:y]) 
            if age <= 50:
                age_50[age] = age_50.get(age, 0) + 1
            elif (age >= 50 & age < 80):
                age50_80[age] = age50_80.get(age, 0) + 1
            elif age >= 80:
                age_80[age] = age_80.get(age, 0) + 1


dicts = age_50, age50_80, age_80
    with open('just for test.csv', 'w') as ofile:
        writer = csv.writer(ofile, delimiter=',')
        writer.writerow(["age_50",  "age50_80",  "age_80"])
        for d in dicts:
            for key in d.items():
                if key in d.keys():
                   enter code here writer.writerow(key, d[key])

它只写没有任何数据的标题。我该如何处理？