'Renders list of descriptors for all the flows.'

def Handle(self, args, token=None):

    result = []
    for name in sorted(flow.GRRFlow.classes.keys()):
        cls = flow.GRRFlow.classes[name]
        if (not getattr(cls, 'category', None)):
            continue
        try:
            if self.legacy_security_manager:
                self.legacy_security_manager.CheckIfCanStartFlow(token, name)
        except access_control.UnauthorizedAccess:
            continue
        result.append(ApiFlowDescriptor().InitFromFlowClass(cls, token=token))
    return ApiListFlowDescriptorsResult(items=result)
