When I visit http://host/app/xxx/new?args, what does Frappe do specifically?

Hello everyone!!
I want Python to manage new form data based on args from url.
Currently, I’m using frappe.call in JavaScript to send a request to Python, which returns the data. However, when I use frm.set_value in JavaScript to set the fields, it triggers field events that I don’t want.
So is there a way for Python to set the fields and have the web side just display the form?

Best Regards

I found function call order, still not find where to add default field value. anyone help me??
d:\frappe\frappe-bench\apps\frappe\frappe\app.py.application
("GET", "HEAD", "POST"):

  1. d:\frappe\frappe-bench\apps\frappe\frappe\website\serve.py.get_response
  2. d:\frappe\frappe-bench\apps\frappe\frappe\website\path_resolver.py.resolve
  3. d:\frappe\frappe-bench\apps\frappe\frappe\website\page_renderers\not_found_page.py
  4. d:\frappe\frappe-bench\apps\frappe\frappe\website\page_renderers\template_page.py.get_html

and then puzzled. :smirk: