todo-insert-category-line
todo-insert-category-line is a compiled Lisp function in `todo-mode.el
'.
(todo-insert-category-line CAT &optional NONUM)
Insert button with category CAT's name and item counts.
With non-nil argument NONUM show only these; otherwise, insert a
number in front of the button indicating the category's priority.
The number and the category name are separated by the string
which is the value of the user option
`todo-categories-number-separator'.