<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def validate_disconnect(self, account, accounts):
 """ Validate whether or not the socialaccount account can be safely disconnected. """

        if len(accounts) == 1:
            # No usable password would render the local account unusable
            if not account.user.has_usable_password():
                raise ValidationError(_("Your account has no password set"
                                        " up."))
            # No email address, no password reset
            if app_settings.EMAIL_VERIFICATION \
                    == EmailVerificationMethod.MANDATORY:
                if EmailAddress.objects.filter(user=account.user,
                                               verified=True).count() == 0:
                    raise ValidationError(_("Your account has no verified"
                                            " e-mail address."))