docs: def get(name, fallback='ssh'):
      """
      Retrieve the matching backend class from a string. If no backend can be
      matched, it raises an error.
  
      >>> get('ssh')
      <class 'remoto.backends.BaseConnection'>
      >>> get()
      <class 'remoto.backends.BaseConnection'>
      >>> get('non-existent')
      <class 'remoto.backends.BaseConnection'>
      >>> get('non-existent', 'openshift')
      <class 'remoto.backends.openshift.OpenshiftConnection'>
      """
      mapping = {
          'ssh': ssh.SshConnection,
          'oc': openshift.OpenshiftConnection,
          'openshift': openshift.OpenshiftConnection,
          'kubernetes': kubernetes.KubernetesConnection,
          'k8s': kubernetes.KubernetesConnection,
          'local': local.LocalConnection,
          'popen': local.LocalConnection,
          'localhost': local.LocalConnection,
          'docker': docker.DockerConnection,
          'podman': podman.PodmanConnection,
      }
      if not name:
          # fallsback to just plain local/ssh
          name = 'ssh'
  
      name = name.strip().lower()
      connection_class = mapping.get(name)
      if not connection_class:
          logger.warning('no connection backend found for: "%s"' % name)
          if fallback:
              logger.info('falling back to "%s"' % fallback)
              # this assumes that ``fallback`` is a valid mapping name
              return mapping.get(fallback)
      return connection_class