将带有元祖的列表变成字典:
dial_codes =[
(86,'China'),
(81,'Japan'),
(1,'United States'),
(7,'Russia'),
(880,'Bangladesh'),
]
country_code = {country: code for code , country in dial_codes}
print(country_code)
#output:{'China': 86, 'Japan': 81, 'United States': 1, 'Russia': 7, 'Bangladesh': 880}
将key, value(无重复) 对换:
{code:country.upper() for country, code in country_code.items() if code <66}
#output: {1: 'UNITED STATES', 7: 'RUSSIA'}