<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _regenerate_secret_key(self):
 """Regenerate secret key http://www.mediafire.com/developers/core_api/1.3/getting_started/#call_signature """

        # Don't regenerate the key if we have none
        if self._session and 'secret_key' in self._session:
            self._session['secret_key'] = (
                int(self._session['secret_key']) * 16807) % 2147483647