module Hashie::Extensions::IndifferentAccess

is injecting itself into member hashes.
their proper indifferent state. Used when IndifferentAccess
Iterates through the keys and values, reconverting them to

def convert!
  keys.each do |k| # rubocop:disable Performance/HashEachMethods
    regular_writer convert_key(k), indifferent_value(regular_delete(k))
  end
  self
end