class Select_Edges(Operator):
    bl_idname = "mesh.select_edge"
    bl_label = "Select Edges"
    bl_options = {'REGISTER', 'UNDO'}

    def invoke(self, context, event):
        if bpy.context.object.type == "MESH":
            bpy.ops.object.mode_set(mode='EDIT') # Enter edit mode if we're not already there and change the selction mode to FACE
            bpy.ops.mesh.select_mode(use_extend=False, use_expand=False, type='EDGE')
        return {'FINISHED'}