DOMForm help me

[vitvn]

response = urlopen("https://www.lingq.com/accounts/login/")
#response = urlopen("http://www.google.com.vn")
window = ParseResponse(response)
window.document  # HTML DOM Level 2 HTMLDocument interface
forms = window._htmlforms  # list of objects supporting ClientForm.HTMLForm i/face
form = forms[1]

print form

#print form

control = form.find_control("password")

form["password"] = 'password'

control = form.find_control("username")
form["username"] = 'username'
response2 = urlopen(form.click())
for form in forms:
 print form

but it can't click to submit button

<POST [url]https://www.lingq.com/accounts/login/[/url] application/x-www-form-urlencoded
  <TextControl(username=)>
  <PasswordControl(password=)>
  <SubmitControl(<None>=Login) (readonly)>
  <HiddenControl(next=) (readonly)>>
<GET [url]https://www.lingq.com/accounts/login/[/url] application/x-www-form-urlencoded
  <SelectControl(<None>=[*en, de, ru, ja, es, fr, it, pt, zh-cn, zh-tw, ko, sv, nl])>>
<POST [url]https://www.lingq.com/accounts/login/[/url] application/x-www-form-urlencoded
  <TextControl(username=username)>
  <PasswordControl(password=password)>
  <SubmitControl(<None>=Login) (readonly)>
  <HiddenControl(next=) (readonly)>>
>Exit code: 0

help me

thank