'Remove all callbacks from the stack by a prefix. Returns True
if keys were there to be removed
:param str or int prefix: The prefix for keeping track of callbacks with
:rtype: bool'

@sanitize_prefix
def cleanup(self, prefix):

    LOGGER.debug('Clearing    out    %r    from    the    stack', prefix)
    if ((prefix not in self._stack) or (not self._stack[prefix])):
        return False
    del self._stack[prefix]
    return True
