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: patchinfo.rb
    path of file: ./repos/open-build-service/src/api/app/models
    
    the code of the file until where you have to start completion: # a Patchinfo lives in a Project, but is not a package - it represents a special file
# in a update package

# if you wonder it's not a module, read http://blog.codeclimate.com/blog/2012/11/14/why-ruby-class-methods-resist-refactoring
class Patchin
    
  def verify_data(project, raw_post)
    @project = project
    data = Xmlhash.parse(raw_post)
    # check the packager field
    User.find_by_login!(data['packager']) if data['packager']
    # valid tracker?
    data.elements('issue').each do |i|
      tracker = IssueTracker.find_by_name(i['tracker'])
      raise TrackerNotFound, "Tracker #{i['tracker']} is not registered in this OBS instance" unless tracker

      issue = Issue.new(name: i['id'], issue_tracker: tracker)
      raise Issue::InvalidName, issue.errors.full_messages.to_sentence unless issue.valid?
    end
    # are releasetargets specified ? validate that this project is actually defining them.
    data.elements('releasetarget') { |r| check_releasetarget!(r) }
  end