当使用python将记录写入csv时，如何在不写入csv中存在的所有记录的情况下删除此输出的空白行？

Question

我一直在尝试使用python从我的csv文件中的记录之间删除空白行而不擦除整个电子表格。

import csv, os

def display(file):              # this procedure displays file and returns the last ID
    f=csv.reader(open(file,'r'))
    for i in f:
        ID = i[0]
        print i
    return ID

def newentry(file, rec):            # this writes the rec to the file
    f=csv.writer(open(file,'a'))
    f.writerow(rec)

#--------------------------------------
''' this is the main program that -
1. creates the next ID value
2. takes the inputs for record to be written
3. define the record in the correct order
'''

#---to append a new entry with the next value for ID

n = input("Enter number of records to add:")
for i in range(n):
    ID=int(display('records.csv'))+1
    fname=raw_input("Please enter the First Name:")
    sname=raw_input("Please enter the Surname:")
    hnumber=raw_input("Please enter the house name or number:")
    street=raw_input("Please enter the name of the street:")
    area=raw_input("Please enter the area:")
    county=raw_input("Please enter the County:")
    pcode=raw_input("Please enter the Postcode:")
    tel=raw_input("Please enter the contact number:")
    rec=(ID,fname,sname,hnumber,street,area,county,pcode,tel)
    newentry('records.csv', rec)


#---- to display the file for confirmation

display('records.csv')

这会创建如下记录：

1,dave,davidson,1,avenue,somewhere,somewhere,pppppp,0111111111

2,jeff,jefferson,3,street,overthere,overhere,tttttt,0222222222

但我需要它在Excel中显示如下：

1,dave,davidson,1,avenue,somewhere,somewhere,pppppp,0111111111
2,jeff,jefferson,3,street,overthere,overhere,tttttt,0222222222

我做错了什么？