Error notification_config of

I’ve used notification_config of the hooks file,and build the notification file and write the code
def get_notification_config():

frappe.msgprint("your notification message")
return {
    "for_doctype": {
        "mchStaff": {"no_of_renewal":["=", '3'], "end_of_the_contract": ["<", frappe.utils.add_days(frappe.utils.nowdate(), 5)]}

first problem: why the msgprint doesn’t appear?
second : the result is a red label with the module name;when clicked;it appears a list of records that have the filter, but why the filter duplicated???

plz any one can help