如何按常见项目对元组进行分组并查找每组的平均值

我有一个名为的元组列表data:

data = [('A', 2), 
        ('B', 2), ('B', 4), ('B', 6), ('B', 8), ('B', 6), ('B', 4), ('B', 3),
        ('C', 10), ('C', 10), ('C', 10),
        ('D', 12),
        ('E', 12),
        ('F', 10), ('F', 8), ('F', 6)]
average = []

我想要每个相同字母的平均值：

预期输出：

average = [('A', 2), ('B', 5), ('C', 10), ('D', 12), ('E', 12), ('F', 8)]

这是一个带有默认字典的选项：

from collections import defaultdict
avg = defaultdict(lambda :{'count': 0, 'sum': 0})
​
# calculate the sum and count for each key
for k, v in data:
    avg[k]['count'] += 1
    avg[k]['sum'] += v

# calculate the average
[(k, v['sum']/v['count']) for k, v in avg.items()]

#[('A', 2.0),
# ('D', 12.0),
# ('F', 8.0),
# ('E', 12.0),
# ('B', 4.714285714285714),
# ('C', 10.0)]