cleanup.py

# -*- coding: utf-8 -*-

import argparse

def reformat_table(content, start, end):
    tabledata = [line.split(" | ") for line in content[start:end]]
    tabledata.pop(1)
    lengths = [0] * len(tabledata[0])
    
    for row in tabledata:
        lengths = map(
            lambda pair: max(pair),
            zip(lengths, [len(cell) for cell in row])
        )
    
    newtable = []
    for row in tabledata:
        newtable.append(
            " | ".join(
                [cell.ljust(lengths[i]) for i, cell in enumerate(row)]
            )
        )
    
    newtable[1:1] = [" | ".join(["-" * l for l in lengths])]
    
    content[start:end] = newtable

def clean_tables(content):
    start = 0
    end = 0
    
    for i, line in enumerate(content):
        if "- |" in line:                    # Find the component which defines a table
            start = i - 1
        elif start != 0 and " |" not in line:
            end = i
            
            reformat_table(content, start, end)
            
            start = 0
            end = 0

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="This is an example cleanup script")
    parser.add_argument("-f", "--file", metavar="File", type=argparse.FileType("r"), dest="file", required=True, help="Specifies the file to be cleaned")
    
    args = parser.parse_args()
    
    content = [line.rstrip() for line in args.file]
    clean_tables(content)
    
    for line in content:
        print(line)

Example for creating a script to cleanup Markdown files to ensure that tables are consistently formatted. Tested with Python 2.7.10