```ruby
module Delocalize
  module ParameterDelocalizing
    def delocalize(options)
      delocalize_hash(self, options)
    end

  private

    def delocalize_hash(hash, options, key_stack = [])
      hash.each do |key, value|
        key_stack = [*key_stack, key] # don't modify original key stack!

        hash[key] = value.is_a?(Hash) ?
          delocalize_hash(hash[key], options, key_stack) :
          delocalize_parse(options, key_stack, value)
      end
    end

    def delocalize_parse(options, key_stack, value)
      parser = delocalize_parser_for(options, key_stack)
      parser ? parser.parse(value) : value
    end

    def delocalize_parser_for(options, key_stack)
      parser_type = key_stack.reduce(options) { |h, key| h.stringify_keys[key.to_s] }
      return unless parser_type

      parser_name = "delocalize_#{parser_type}_parser"
      respond_to?(parser_name, true) ?
        send(parser_name) :
        raise(Delocalize::ParserNotFound.new("Unknown parser: #{parser_type}"))
    end

    def delocalize_number_parser
      @delocalize_number_parser ||= Parsers::Number.new
    end

    def delocalize_time_parser
      @delocalize_time_parser ||= Parsers::DateTime.new(Time)
    end

    def delocalize_date_parser
      @delocalize_date_parser ||= Parsers::DateTime.new(Date)
    end

  end
end
```

Fix bug with modified key stack
user
```ruby
module Delocalize
  module ParameterDelocalizing
    def delocalize(options)
      delocalize_hash(self, options)
    end

  private

    def delocalize_hash(hash, options, base_key_stack = [])
      hash.each do |key, value|
        key_stack = [*base_key_stack, key] # don't modify original key stack!

        hash[key] = value.is_a?(Hash) ?
          delocalize_hash(value, options, key_stack) :
          delocalize_parse(options, key_stack, value)
      end
    end

    def delocalize_parse(options, key_stack, value)
      parser = delocalize_parser_for(options, key_stack)
      parser ? parser.parse(value) : value
    end

    def delocalize_parser_for(options, key_stack)
      parser_type = key_stack.reduce(options) { |h, key| h.stringify_keys[key.to_s] }
      return unless parser_type

      parser_name = "delocalize_#{parser_type}_parser"
      respond_to?(parser_name, true) ?
        send(parser_name) :
        raise(Delocalize::ParserNotFound.new("Unknown parser: #{parser_type}"))
    end

    def delocalize_number_parser
      @delocalize_number_parser ||= Parsers::Number.new
    end

    def delocalize_time_parser
      @delocalize_time_parser ||= Parsers::DateTime.new(Time)
    end

    def delocalize_date_parser
      @delocalize_date_parser ||= Parsers::DateTime.new(Date)
    end

  end
end
```
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