Dynamic enum shenanigans

gistfile1.txt

import bpy
from bpy.props import EnumProperty


def Dynamic_Enum(context):
    Dynamic_Enum.enum_items = []
    for line in bpy.data.texts['Text'].lines:
        Dynamic_Enum.enum_items.append((line.body, line.body,""))

def pick_enum(self, context):
    # Only toggle if the user chose someting else than 1st option
    self.picked_enum = self.Dynamic_Enum != "-1000"

class MyProperties(bpy.types.PropertyGroup):
    picked_enum: bpy.props.BoolProperty(default=False)
    Dynamic_Enum : EnumProperty(
        name = "Enumarator_2 / Dropdown",
        description = "dynamic items",
        items=lambda self, context: Dynamic_Enum.enum_items,
        update=pick_enum
        )

class ADDONNAME_PT_main_panel(bpy.types.Panel):
    bl_label = "My Panel"
    bl_idname = "ADDONNAME_PT_main_panel"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = "Test Tab"

    def draw(self, context):
        layout = self.layout
        mytool = context.scene.my_tool
        Dynamic_Enum(context) # Update enum items before drawing them
        if not mytool.picked_enum:  # Prepend our menu option if the user never picked an item
            Dynamic_Enum.enum_items = [("-1000", "Choose Something", "")] + list(Dynamic_Enum.enum_items)
        layout.prop(mytool, "Dynamic_Enum", text= "dynamic")

    

classes = [MyProperties, ADDONNAME_PT_main_panel]
 
 
def register():
    for cls in classes:
        bpy.utils.register_class(cls)
    bpy.types.Scene.my_tool = bpy.props.PointerProperty(type=MyProperties)
 
if __name__ == "__main__":
    register()