Write list of list to CSV?

[buran]

the only problem I see is that dlist is already list of lists. But this will not prevent writing to file (although it may be not what you want:

Output:
device1,HundredGigE0/2/0/0,"['ALPHANUMERICWITHCHARAC;;;', 'ALPHANUMERICWITHCHARAC;;;', 'ALPHANUMERICWITHCHARAC;;;']"
,HundredGigE0/2/0/0.242,
,HundredGigE0/2/0/0.244 l2transport,
,HundredGigE0/2/0/1,
,HundredGigE0/2/0/0.244,
device1,TenGigabitEthernet1/1/0.138,['ALPHANUMERICWITHCHARAC;;;']
device1,TenGigE0/1/0/15,['ALPHANUMERICWITHCHARAC;;;']

note that lst column is str repr of a list.
If you make it like this

import itertools
import csv
opo = ['device1', 'device1', 'device1']
intfname = [['HundredGigE0/2/0/0', 'HundredGigE0/2/0/0.242', 'HundredGigE0/2/0/0.244 l2transport', 'HundredGigE0/2/0/1', 'HundredGigE0/2/0/0.244'], ['TenGigabitEthernet1/1/0.138'], ['TenGigE0/1/0/15']]
descname = [['ALPHANUMERICWITHCHARAC;;;', 'ALPHANUMERICWITHCHARAC;;;', 'ALPHANUMERICWITHCHARAC;;;'], ['ALPHANUMERICWITHCHARAC;;;'], ['ALPHANUMERICWITHCHARAC;;;']]# ['0/2/0/0info1', '0/2/0/0.242info2', '0/2/0/0.244info3']

opo = [[ele] for ele in opo]
 
## EXPORT AS CSV
with open('intlist.csv', 'w', newline='') as updatecsv:
    write = csv.writer(updatecsv, delimiter=',',lineterminator='\n')
    for cols in zip(opo,intfname,descname):
        rows = itertools.zip_longest(*cols, fillvalue='')
        write.writerows(rows)
updatecsv.close()
print ("Done...")

the output will be

Output:
device1,HundredGigE0/2/0/0,ALPHANUMERICWITHCHARAC;;;
,HundredGigE0/2/0/0.242,ALPHANUMERICWITHCHARAC;;;
,HundredGigE0/2/0/0.244 l2transport,ALPHANUMERICWITHCHARAC;;;
,HundredGigE0/2/0/1,
,HundredGigE0/2/0/0.244,
device1,TenGigabitEthernet1/1/0.138,ALPHANUMERICWITHCHARAC;;;
device1,TenGigE0/1/0/15,ALPHANUMERICWITHCHARAC;;;

Note that desc values go to first three lines, I don't know if this is correct

What I try to say is if the print output is OK, then second part should work too (i.e. the lists are populated with values, not empty)

you can make opo list of lists by design, when you create it in the first place.