#! python3
 
data = [
	['spanish', 'web2.0', 'e-learning', 'education', 'social', 'spain', 'tools', 'learning', 'google', 'e-learning2.0'],
	['education', 'technology', 'learning', 'classroom', '%22educational%20technology%22', 'google', 'teaching', 'collaboration', 'students', 'web2.0'],
	['education'],
	['technology']
]
 
search_table = {}
 
for i, tag_list in enumerate(data):
	for tag in tag_list:
		if tag not in search_table:
			search_table[tag] = set()
		search_table[tag].add(i)
 
# How many people have `technology`?
print(len(search_table["technology"]))
 
# How many people have both `technology`, `education`?
print(len(search_table["technology"] & search_table["education"]))
 

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