def all_hosts_in(file)
      servers = []
      file.each do |line|
        if line.include?('Host ')
          servers << line.sub('Host ', '').strip
        end
      end
      servers
    end
def all_hosts_in(file)
      servers = []
      file.each do |line|
        if line.include?('Host ')
          servers << line.sub('Host ', '').strip
        end
      end
      servers
    end
Returns all the alias names of in the file