Gmail: Extract Blocked Attachments From Original Email

import os
import sys
import email

"""
SOURCE: https://spapas.github.io/2014/10/23/retrieve-gmail-blocked-attachments/

1. In gmail, find the email that has the blocked attachments you want to download.

2. Click the dropdown arrow located top-right of that email.
   Click "Show original"

3. Click "Download Original".

4. Copy the file to this folder.

5. Open command prompt to this folder
   Run this: $ python get_attachments.py original_msg.txt
"""

def ensure_nested_dir(nested_dir):
    this_py_file = os.path.realpath(__file__)
    directory = os.path.join(os.getcwd(), nested_dir)
    if not os.path.exists(directory):
        os.makedirs(directory)

if __name__=='__main__':
    if len(sys.argv)<2:
        print("Please enter a file to extract attachments from")
        sys.exit(1)

    original_msg_dir = os.getcwd()
    nested_dir = "Extracted Email Attachments"
    ensure_nested_dir(nested_dir)
    os.chdir(nested_dir)

    msg = email.message_from_file(open(os.path.join(original_msg_dir, sys.argv[1])))
    for pl in msg.get_payload():
        if pl.get_filename(): # if it is an attachment
            open(pl.get_filename(), 'wb').write(pl.get_payload(decode=True))