import pandas as pd
df = pd.read_csv(csv_file, encoding="gbk")
new_csv = new_csv_file
newdf_list = []
for i in range(0,len(df.values)):
# 得到单元格值
value = df.iloc[i,3]
# 筛选条件
if value <= 1:
newdf_list.append(df.iloc[i,:])
# 将列表转换为DataFrame格式
newdf = pd.DataFrame(newdf_list)
newdf.to_csv(new_csv)