Error while using tabulate "TypeError: 'int' object is not iterable"

so, I was using tabulate to format my data in my latest project. But, it keeps giving this error and I'm not able to understand the reason behind it. Here's the code:

   from datetime import date
   from tabulate import tabulate
   records = []
   sno = [0,1]
   jades = [0,1]
   events = ['0',1]
   dates = ['0',1]
   for i in range(0, len(jades)):
      records.append([sno[i], jades[i], events[i], dates[i]])
        
   print(records)
   record = records[-1]
   print(record)
   print(tabulate(record, headers=["Sno.", "Jades", "Event", "Date"], tablefmt='simple'))

here's the output:

[[0, 0, '0', '0'], [1, 1, 1, 1]]
[1, 1, 1, 1]
Traceback (most recent call last):
  File "/home/kartik/Desktop/discord-bot/Rem.py", line 16, in <module>
    print(tabulate(record, headers=["Sno.", "Jades", "Event", "Date"], tablefmt='simple'))
  File "/home/kartik/.local/lib/python3.8/site-packages/tabulate.py", line 1426, in tabulate
    list_of_lists, headers = _normalize_tabular_data(
  File "/home/kartik/.local/lib/python3.8/site-packages/tabulate.py", line 1103, in _normalize_tabular_data
    rows = list(map(list, rows))
TypeError: 'int' object is not iterable

Do note that the code which i posted is just the part which i found was causing the error. Those line numbers may differ.

I tried figure out myself but the only thing I could come up with was this code:

record = [records[-1]]

I converted that last records into list of its own.

Please, help me understand the reason behind it. I'm kind of a beginner at python so, my question might be dumb.

Thank you in advance!

Solution

According to the documentation, the first parameter to tabulate is an iterable of iterables or similar, like a spreadsheet. You need both rows and columns. What you passed in was just one list, so internally, it first grabs the first element ("1" in your case), thinks of that as a row, and then tries to iterate through each column, which is where the exception is raised.

When you wrap it in another set of brackets, like:

record = [records[-1]]

Then you're actually having [[1, 1, 1, 1]], which is one row (the outer bracket) containing four columns (the inner bracket).

I've never used this library, so I might have rows/columns switched here, but the concept is the same.