import 
as pd
import numpy as np
import matplotlib.pyplot as plt
#df.to_excel('C:Users/history/Desktop/Python成绩.xlsx', sheet_name='dfg')
df = pd.read_excel('C:/Users/history/Desktop/Python成绩.xlsx', index_col=None, na_values=['NA'])
df.to_excel('C:/Users/history/Desktop/Python.xlsx', sheet_name='dfg')
print(df)
