import collections
my_result = collections.defaultdict(int)

my_list = [[('Hello', 'Hey')], [('Jane', 'Will')], [('William', 'John')], [('Hello', 'Hey')], [('z', 'q')]]
print("列表的列表是：")
print(my_list)
for elem in my_list:
   my_result[elem[0]] += 1
print("结果是：")
print(my_result)

The list of list is :
[[('Hello', 'Hey')], [('Jane', 'Will')], [('William', 'John')], [('Hello', 'Hey')], [('z', 'q')]]
The result is :
defaultdict(<class 'int'>, {('Hello', 'Hey'): 2, ('Jane', 'Will'): 1, ('William', 'John'): 1, ('z', 'q'): 1})