code: def extract(self, package_name):
          
          for cmd in ['rpm2cpio', 'cpio']:
              if not Cmd.which(cmd):
                  message = '{0} command not found. Install {0}.'.format(cmd)
                  raise InstallError(message)
  
          pattern = '{0}*{1}.rpm'.format(package_name, self.arch)
          rpm_files = Cmd.find('.', pattern)
          if not rpm_files:
              raise InstallError('PRM file not found.')
          cmd = 'rpm2cpio {0} | cpio -idmv'.format(rpm_files[0])
          Cmd.sh_e(cmd)
docs: Extract given package.