import pandas as pd
datafile = 'test.xlsx'
data = pd.read_excel(datafile)
new_data = data[data['用户名称'].str.len()>3]
new_data.to_excel('testfile.xlsx')

import pandas as pd
datafile = 'test.xlsx'
data = pd.read_excel(datafile)
new_data = data[data['用户名称'].str.len()>3]
new_data.to_excel('testfile.xlsx')