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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def save_user(self, request, sociallogin, form=None):
 """ Saves a newly signed up social login. In case of auto-signup, the signup form is not available. """

        u = sociallogin.user
        u.set_unusable_password()
        if form:
            get_account_adapter().save_user(request, u, form)
        else:
            get_account_adapter().populate_username(request, u)
        sociallogin.save(request)
        return u