You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: steps_fetcher.rb
    path of file: ./repos/i-diario/app/services
    
    the code of the file until where you have to start completion: class StepsFetcher
  def initialize(classroom)
    @classroom = classro
    
  def step_by_number(step_number)
    return if school_calendar.blank?

    school_calendar_steps.each do |step|
      return step if step.step_number == step_number.to_i
    end

    nil
  end