correct_open_closed_principle.rb

class ReportSender
  def initialize(report, account)
    @report = report
    @account = account
  end

  def send_report(sender = EmailSender.new)
    sender.send(@account)
  end
end

class ReportGenerator
  # report generation
end

class Sender
  def send(account)
    raise NotImplementedError
  end
end

class EmailSender < Sender
  def send(account)
    # implementation for Email
  end
end

class SmsSender < Sender
  def send(account)
    # implementation for SMS
  end
end

report = ReportGenerator.new(data).generate
ReportSender.new(report, account).send_report(SmsSender.new)