docs: def eval(self, command):
          """ Execute Tcl command.
  
          Write the command to tcl script (.tcl) log file.
          Execute the command.
          Write the command and the output to general (.txt) log file.
  
          :param command: Command to execute.
          :returns: command raw output.
          """
  
          if self.logger.handlers:
              self.logger.debug(command.decode('utf-8'))
          if self.tcl_script:
              self.tcl_script.info(command)
          self.rc = self.tcl_interp.eval(command)
          if self.logger.handlers:
              self.logger.debug('\t' + self.rc.decode('utf-8'))
          return self.rc