code: def execute_wait(self, cmd, walltime=2, envs={}):
          ''' Synchronously execute a commandline string on the shell.
  
          Args:
              - cmd (string) : Commandline string to execute
              - walltime (int) : walltime in seconds
  
          Kwargs:
              - envs (dict) : Dictionary of env variables
  
          Returns:
              - retcode : Return code from the execution, -1 on fail
              - stdout  : stdout string
              - stderr  : stderr string
  
          Raises:
          None.
          '''
  
          # Execute the command
          stdin, stdout, stderr = self.ssh_client.exec_command(
              self.prepend_envs(cmd, envs), bufsize=-1, timeout=walltime
          )
          # Block on exit status from the command
          exit_status = stdout.channel.recv_exit_status()
          return exit_status, stdout.read().decode("utf-8"), stderr.read().decode("utf-8"f execute_wait(self, cmd, walltime=2, envs={}):
          ''' Synchronously execute a commandline string on the shell.
  
          Args:
              - cmd (string) : Commandline string to execute
              - walltime (int) : walltime in seconds
  
          Kwargs:
              - envs (dict) : Dictionary of env variables
  
          Returns:
              - retcode : Return code from the execution, -1 on fail
              - stdout  : stdout string
              - stderr  : stderr string
  
          Raises:
          None.
          '''
  
          # Execute the command
          stdin, stdout, stderr = self.ssh_client.exec_command(
              self.prepend_envs(cmd, envs), bufsize=-1, timeout=walltime
          )
          # Block on exit status from the command
          exit_status = stdout.channel.recv_exit_status()
          return exit_status, stdout.read().decode("utf-8"), stderr.read().decode("utf-8")
docs: Synchronously execute a commandline string on the shell.
  
          Args:
              - cmd (string) : Commandline string to execute
              - walltime (int) : walltime in seconds
  
          Kwargs:
              - envs (dict) : Dictionary of env variables
  
          Returns:
              - retcode : Return code from the execution, -1 on fail
              - stdout  : stdout string
              - stderr  : stderr string
  
          Raises:
          None.