"""
    方案一
"""
file = open('./dict.txt')
def func(target):
    # for line in file:
    #     end = line.find(" ")
    #     if line[0:end] == target:
    #         file.close()
    #         return line
    #     if target > line[0:end]:
    #         file.close()
    #         return None
    pass

print(func('a'))




"改"

