Add a 'sticky note' at position 'point'.

def addTextAnnot(self, point, text):
        """Add a 'sticky note' at position 'point'."""
        CheckParent(self)

        val = _fitz.Page_addTextAnnot(self, point, text)

        if not val: return
        val.thisown = True
        val.parent = weakref.proxy(self)
        self._annot_refs[id(val)] = val

        return val