把frame.append改成pandas.concat

Question

all_data = pd.DataFrame()
for i in range(1, 26):
all_data = all_data.append(dangdang(i),ignore_index=True)
all_data.to_excel('当当图书畅销榜单.xlsx', index=False)

报错FutureWarning: The frame.append method is deprecated and will be removed from pandas in a future version. Use pandas.concat instead.
all_data = all_data.append(dangdang(i),ignore_index=True)

求帮忙改一下代码