The script_ids.json file is simply a list of script id strings.

Update Multiple Google Apps Script projects.py

import json
import os
import subprocess

# replace with id of your template
template_id_string = '{ "scriptId": "1emazMPaUkLHXbgbEF0nOKwU275gL7H5cwue909bVMtkp2czm_tB5XYwH" }'

def run_update(id):
    new_clasp_string = f'{{ "scriptId": "{id}" }}'
    # overwrite the clasp file
    with open(os.path.join(os.path.dirname(__file__), ".clasp.json"), "w") as f:
        f.write(new_clasp_string)
    # push to the script
    subprocess.run(["clasp", "push"])
    
def push_updates(script_id=None):
    if script_id:
        run_update(script_id)
    else:
        with open(os.path.join(os.path.dirname(__file__), "script_ids.json")) as f:
            ids = json.load(f)
            
        id_count = len(ids)
        for i, id in enumerate(ids):
            print(id)
            print(f'id {i + 1} of {id_count}')
            run_update(id)
            
    # revert back to template file id  
    with open(os.path.join(os.path.dirname(__file__), ".clasp.json"), "w") as f:
            f.write(template_id_string)
            
    subprocess.run(["say", "'done updating pricing tool scripts'"])
    
if __name__ == "__main__":
    # single script id
    # push_updates("1VNWZZUxr8dUl03SCKqVljPAZGawa711m-VcjAA8DGJnHNdHQ5Igp8daX")
    # all
    push_updates()