':param vuln_obj: The vuln to exploit.
:return: The shell object based on the vulnerability that was passed as
a parameter.'

def _generate_shell(self, vuln_obj):

    if self._verify_vuln(vuln_obj):
        shell_obj = DAVShell(vuln_obj, self._uri_opener, self.worker_pool, self._exploit_url)
        return shell_obj
    else:
        return None
