code: def mount(self):
          
          if self.mounted:
              return
  
          self._mount_point_local_create()
  
          if len(self.system.mount_opts) == 0:
              sshfs_opts = ""
          else:
              sshfs_opts = " -o %s" % " -o ".join(self.system.mount_opts)
  
          if self.system.auth_method == self.system.AUTH_METHOD_PUBLIC_KEY:
              ssh_opts = '-o PreferredAuthentications=publickey -i %s' % self.system.ssh_key
          elif self.system.auth_method:
              ssh_opts = '-o PreferredAuthentications=%s' % self.system.auth_method
          else:
              ssh_opts = '-o PreferredAuthentications=password'
  
          cmd = ("{cmd_before_mount} &&"
                 " sshfs -o ssh_command="
                 "'ssh -o ConnectTimeout={timeout} -p {port} {ssh_opts}'"
                 " {sshfs_opts} {user}@{host}:{remote_path} {local_path}")
          cmd = cmd.format(
              cmd_before_mount = self.system.cmd_before_mount,
              timeout = self.SSH_CONNECT_TIMEOUT,
              port = self.system.port,
              ssh_opts = ssh_opts,
              sshfs_opts = sshfs_opts,
              host = self.system.host,
              user = self.system.user,
              remote_path = self.mount_point_remote,
              local_path = self.mount_point_local,
          )
  
          output = shell_exec(cmd).strip()
  
          if not self.mounted:
              # Clean up the directory tree
              self._mount_point_local_delete()
              if output == '':
                  output = 'Mounting failed for a reason unknown to sftpman.'
              raise SftpMountException(cmd, output)
docs: Mounts the sftp system if it's not already mounted.