How can you make a selection in a global_form ListControl element using mechanize (python)?

Question

I am working with a food bank in order to help them automatically create an entry for a new guest whenever someone fills out their intake form. In order to create a new guest, the outreach must first be selected. This is done through a ListControl that is part of the global form.

import mechanize
import http.cookiejar

br = mechanize.Browser()
cj = http.cookiejar.LWPCookieJar()
br.set_cookiejar(cj)
br.set_handle_equiv(True)
br.set_handle_gzip(True)
br.set_handle_redirect(True)
br.set_handle_referer(True)
br.set_handle_robots(False)
br.set_handle_refresh(mechanize._http.HTTPRefreshProcessor(), max_time=1)
br.addheaders = [('User-agent', 'Chrome')]


# login

br.open('https://companywebsite.com/login')
br.select_form(nr = 0)
br.form['username'] = 'my_username'
br.form['password'] = 'my_password'
br.submit()


# Deselect the default placeholder value and select the name of the outreach

br.open('https://companywebsite.com/create-new-visit')
br.global_form().find_control(id='outreachSelect').items[0].selected = False
br.global_form().find_control(id='outreachSelect').items[1].selected = True
print(br.global_form().find_control(id='outreachSelect').items)

This is the output that I get. As you can see, the first item is still selected.

[<Item name='0' id=None value='0' selected='selected' contents='Select an Outreach' label='Select an Outreach'>, 
<Item name='558' id=None value='558' contents='Company Name' label='Company Name'>]

This screenshot shows how the website looks

In order for the "Create New Guest" button to work, the "Select an Outreach" dropdown must be changed

Answer 1

After looking at it again, I found that the site was running javascript based on the contents of that dropdown. When the correct option was selected it would make a request to https://companywebsite.com/create-new-visit/set-outreach/?id=config_1.

I was able to solve my problem by making that same request using mechanize and then using the "Create New Guest" button.