Your child class must

  use Object::InsideOut qw(class_insideout);
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instead of

  use base qw(class_insideout);
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From the POD:

Sub-classes (child classes) inherit from base classes (parent classes)
by telling Object::InsideOut what the parent class is:

package My::Sub; {
  use Object::InsideOut qw(My::Parent);
  ...
}
<snip>
Object::InsideOut acts as a replacement for the "base" pragma:  It
loads the parent module(s), calls their "->import()" methods, and sets
up the sub-class's @ISA array.  Therefore, you should not "use base ..
+." yourself
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