TypeError: ListControl, must set a sequence (python error)

Question

I am using Python Mechanize to open a website, fill out a form, and submit that form. It's actually pretty simple. It works until I come across radio buttons and "select" input boxes.

br.open(url)
br.select_form(name="postmsg")
br.form['subject'] = "Is this good for the holidays? "
br.form['message'] = "I'm new to technology."
br.form['E'] = '0'
br.submit()

  br.form['E'] = '0'
  File "build/bdist.linux-x86_64/egg/ClientForm.py", line 2897, in __setitem__
  File "build/bdist.linux-x86_64/egg/ClientForm.py", line 2092, in __setattr__
  File "build/bdist.linux-x86_64/egg/ClientForm.py", line 2100, in _set_value
TypeError: ListControl, must set a sequence

Why am I getting this error? Why can't I set E just like the text boxes? (E is a radio button)

Edit: This is the form, according to Web Developer.

Elements
Index   Id Name Type Value Label Size Maximum Length State
0   subject subject text   35  
2   message message textarea     
3   identity identity select   1  
13   action_btn hidden     
14   _charset_ hidden     
16   r hidden /Stocks_(A_to_Z)/Stocks_G    
9    E radio 0    

Checked
8    E radio 1    
15   .crumb hidden 1n1Yo3MQae3    
7    E radio 2    
17   bn hidden 25263    
6    E radio 3    
5    E radio 4    
4    E radio 5    
12  SubmitCancel SubmitCancel submit Cancel    
1   mbpostthreads threads button Check Existing Topics First    
11  SubmitPost SubmitPost submit Post Message    
10  SubmitPreview SubmitPreview submit Preview Message    
18  yIdCoreIdUser  hidden annamae41g

Answer 1

Radio buttons and Check-boxes can have different behavior then other elements. It depends on their name and id.

If the items have the same name, try doing this:

br.find_control(name="E").value = ["0"]

Another option is:

form.find_control(name="E, kind="list").value = ["0"]

and finally, this might work:

    br["E"] = ["0"]

(I haven't used mechanize in a while so i don't remember exactly).