module ActiveRecord::Inheritance::ClassMethods

def subclass_from_attributes(attrs)

is not self or a valid subclass, raises ActiveRecord::SubclassNotFound
Detect the subclass from the inheritance column of attrs. If the inheritance column value 
def subclass_from_attributes(attrs)
  attrs = attrs.to_h if attrs.respond_to?(:permitted?)
  if attrs.is_a?(Hash)
    subclass_name = attrs[inheritance_column] || attrs[inheritance_column.to_sym]
    if subclass_name.present?
      find_sti_class(subclass_name)
    end
  end
end