pandas将连续持续时间列转换为开始和结束列

我想转换 duration 列到 start 和 end 列。我尝试了下面的代码,它按预期工作,但不是一种完美的方式。

import pandas as pd

def main():
    data = [
        ['A',7],
        ['B',5],
        ['C',5],
        ['D',15],
        ['E',5]
        ]

    df = pd.DataFrame(data,columns=['name','duration'])
    data = []
    for idx,row in df.iterrows():
        name = row['name']
        dur = row['duration']
        if idx == 0:
            start = 0
            end = start + dur
        else:
            start = end
            end = start + dur
        data.append([name,start,dur,end])
    df = pd.DataFrame(data,columns=['name','start','duration','end'])
    print(df)

main()    

例外结果:

   name  start  duration  end
 0    A      0         7    7
 1    B      7         5   12
 2    C     12         5   17
 3    D     17        15   32
 4    E     32         5   37