Converting pip list --outdated to pandas dataframe

convert_table_to_df.py

# This is also applicable to other table which are styled similar.

import pandas as pd

with open("packagelist.txt") as file:
    input_str = file.read()
column_widths = [len(dashes) for dashes in input_str.split("\n")[1].split()]
column_names = input_str.split("\n")[0].split()
data = {key: list() for key in column_names}
for line in input_str.split("\n")[2:]:
    start = 0
    end = 0
    for column_name, column_width in zip(column_names, column_widths):
        end += column_width + 1
        data[column_name].append(line[start:end])
        start = end
    
pd.DataFrame(data)