code: def sign(self, filename):
          
          sign = self.signcmd()
          certificate = self.certificate()
          if not sign:
              log.error('No signcmd defined.')
              return False
          elif not certificate and '{cert}' in sign:
              log.error('No sign certificated defined.')
              return False
  
          log.info('Signing {0}...'.format(filename))
          sign = os.path.expandvars(sign)
          filename = os.path.expandvars(filename)
          cert = os.path.expandvars(certificate)
  
          # let the previous process finish fully, or we might get some file errors
          time.sleep(2)
          return cmdexec(sign.format(filename=filename, cert=cert)) == 0
docs: Signs the filename with the certificate associated with this builder.
          
          :param      filename | <str>
          
          :return     <bool> | success