AttributeError: 'set' object has no attribute 'keys'

Question

I am trying to convert Unix seconds to date and time from a csv file and tried to write the output to the csv file as a new column. I can convert and print the date and time but I cannot write it to the same csv as a new column.

AttributeError: 'set' object has no attribute 'keys'

I tried to write in different ways but stuck. What am I doing wrong?

import pandas as pd

df = pd.read_csv ('C:/New.csv',sep=';')
print (df)

import datetime
import csv


for i in range(0,len(df)):
    row= df.iloc[i]['arrival_unix_seconds']
    a = int(row)
    date = datetime.datetime.utcfromtimestamp(a)
    targetDate = date.strftime("%Y-%m-%d %H:%M:%S")
    #print(targetDate)
    #targetDate.to_csv("b.csv", sep=';', index=False)

with open("New.csv", "a") as inputfile:

title = ["id", "space_id", "arrival_unix_seconds", "departure_unix_seconds", "xml_id", "Arrival_time"]
writer = csv.DictWriter(inputfile, delimiter=';', fieldnames = title)
writer.writerow({"Arrival_time: targetDate"})

Sample data

id;space_id;arrival_unix_seconds;departure_unix_seconds;xml_id;Arrival_time 2950;72729;1619808731;1619809039;22
320;16639;1612627087;1612628433;76
82;3408;1609751088;1609751723;7

Answer 1

Try apply it is way fast than iterating rows one by one

df['arrival_unix_seconds'] = df.arrival_unix_seconds.apply(lambda x: \
    (datetime.datetime.utcfromtimestamp(int(x))).strftime("%Y-%m-%d %H:%M:%S"))

# Save it like this
pd.to_csv('NEW.csv', index=False)

Instead of this

for i in range(0,len(df)):
    row= df.iloc[i]['arrival_unix_seconds']
    a = int(row)
    date = datetime.datetime.utcfromtimestamp(a)
    targetDate = date.strftime("%Y-%m-%d %H:%M:%S")
    #print(targetDate)
    #targetDate.to_csv("b.csv", sep=';', index=False)

with open("New.csv", "a") as inputfile:

title = ["id", "space_id", "arrival_unix_seconds", "departure_unix_seconds", "xml_id", "Arrival_time"]
writer = csv.DictWriter(inputfile, delimiter=';', fieldnames = title)
writer.writerow({"Arrival_time: targetdata"})