def userinfo(phonenumber):
    中国联通 = ['130', '131', '132', '145', '155.156', '785', '186', '176', '175']
    中国移动 = ['134', '135', '136', '137.138', '139', '147', '150', '151', '152', '157', '158', '159', '182', '183',
            '187.188', '178']
    中国电信 = ['133', '153', '180', '181.189', '177', '173', '149']
    num3 = phonenumber[0:3]
    if num3 in 中国联通:
        return "中国联通"
    elif num3 in 中国移动:
        return "中国移动"
    elif num3 in 中国电信:
        return "中国电信"


print(userinfo('13099999999'))
print(userinfo('13499999999'))
print(userinfo('13399999999'))

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