import bpy


class EDMDataPanel(bpy.types.Panel):
  bl_idname = "OBJECT_PT_edmtools"
  bl_label = "EDM Tools"
  bl_space_type = 'PROPERTIES'
  bl_region_type = 'WINDOW'
  bl_context = "data"

  @classmethod
  def poll(cls, context):
    return context.object.type == 'EMPTY'  

  def draw(self, context):
    self.layout.prop(context.object, "is_connector")

class DopeActionProperties(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "EDM Action Properties"
    bl_idname = "OBJECT_PT_dope_action"
    bl_space_type = 'DOPESHEET_EDITOR'
    bl_region_type = 'UI'
    bl_context = "action"

    @classmethod
    def poll(self, context):
        return context.object.animation_data.action != None
    
    def draw(self, context):
        row = self.layout.row()
        row.prop(context.object.animation_data.action, "argument")

def register():
  bpy.utils.register_class(EDMDataPanel)
  bpy.utils.register_class(DopeActionProperties)

def unregister():
  bpy.utils.unregister_class(DopeActionProperties)
  bpy.utils.unregister_class(EDMDataPanel)




#   import bpy

# #bpy.types.Object.is_connector = bpy.props.BoolProperty(
# ##      default=False, 
# #      name="Is Connector?", 
# #      description="Is this empty a connector object?")

# 

# def register():
#     bpy.utils.register_class(HelloWorldPanel)


# def unregister():
#     bpy.utils.unregister_class(HelloWorldPanel)


# if __name__ == "__main__":
#     register()

@@ -397,18 +397,16 @@
 Panel):%0A
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@@ -453,18 +453,16 @@
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@@ -492,18 +492,16 @@
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- 
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 bl_idnam
@@ -528,18 +528,16 @@
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   bl_spa
@@ -565,18 +565,16 @@
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   bl_reg
@@ -589,18 +589,16 @@
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   bl_con
@@ -614,18 +614,16 @@
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@@ -631,18 +631,16 @@
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 def poll
@@ -654,24 +654,31 @@
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@@ -727,19 +727,61 @@
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@@ -799,20 +799,16 @@
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@@ -827,20 +827,16 @@
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Fix error in argument panel polling