Python: ‘tuple’ object is not callable

This can be a bit of an obscure error, if you run into it…  It looks like this:

File ".../CCRM/", line 202, in Page_Update
    ('Nav1'       , Data.Nav1),
TypeError: 'tuple' object is not callable

In reality, it’s typically caused by accidentally forgetting a comma from the line before:

    Page_MNID = App.DB.Value('''
      WHERE True
        AND "Page_MNID" = $Page_MNID
      ('ScriptPath' , Data.ScriptPath)
      ('Nav1'       , Data.Nav1),
      ('Nav2_Icon'  , Data.Nav2_Icon),
      ('Nav2_Label' , Data.Nav2_Label),
      ('Title'      , Data.Title),
      ('Active'     , Data.Active),
      Page_MNID     = Data.Page_MNID,

Notice that line 9 is missing a comma at the end?  That causes python to see this:

tuple_object = ("ScriptPath", Data.ScriptPath")
tuple_object("Nav1" , Data.Nav1)  #eg, next tuple looks like params

Solution?  Just add the comma :)