```ruby
class Ey::Core::Client
  class Real
    def get_costs(params={})
      request(
        "url"  => params["url"],
        "path" => "/accounts/#{params["id"]}/costs"
      )
    end
  end

  class Mock
    def get_costs(params={})
      extract_url_params!(params)

      response(
        :body   => {"costs" => self.data[:costs]},
        :status => 200
      )
    end
  end
end
```

Change request hash to symbols
user
```ruby
class Ey::Core::Client
  class Real
    def get_costs(params={})
      request(
        :url  => params["url"],
        :path => "/accounts/#{params["id"]}/costs"
      )
    end
  end

  class Mock
    def get_costs(params={})
      extract_url_params!(params)

      response(
        :body   => {"costs" => self.data[:costs]},
        :status => 200
      )
    end
  end
end
```
assistant