Toggle the IK on a armature in Blender Python

bpy_toggle_armature_ik.py

import bpy
from bpy.props import IntProperty, FloatProperty
from bpy.types import Armature, PoseBone, KinematicConstraint, Object


def ik_constraints(armature: Object):
    assert type(armature.data) is Armature
    return (constraint for pbone in armature.pose.bones
                       for constraint in pbone.constraints
                       if type(constraint is KinematicConstraint))


class ToggleIK(bpy.types.Operator):
    """Disable/Enable the IK of the selected skeleton"""
    bl_idname = "object.toggle_ik_skeleton"
    bl_label = "Toggle IK on Skeleton"

    @classmethod
    def poll(Cls, context):
        return type(context.object.data) is Armature and context.mode == "POSE"

    def invoke(self, context, event):
        state = any(constraint.enabled for constraint in ik_constraints(context.object))
        for constraint in ik_constraints(context.object):
            constraint.enabled = not state
        if state:
            self.report({'INFO'}, "Disabled")
        else:
            self.report({'INFO'}, "Enabled")
        return {'FINISHED'}


def menu_func(self, context):
    self.layout.operator(ToggleIK.bl_idname, text=ToggleIK.bl_label)


def register():
    bpy.utils.register_class(ToggleIK)
    bpy.types.VIEW3D_MT_object.append(menu_func)


def unregister():
    bpy.utils.unregister_class(ToggleIK)
    bpy.types.VIEW3D_MT_object.remove(menu_func)


if __name__ == "__main__":
    register()