code: def _is_single_paragraph(node: nodes.field_body) -> bool:
      """True if the node only contains one paragraph (and system messages)."""
      if len(node) == 0:
          return False
      elif len(node) > 1:
          for subnode in node[1:]:  # type: Node
              if not isinstance(subnode, nodes.system_message):
                  return False
      if isinstance(node[0], nodes.paragraph):
          return True
      return False
  
imports: from __future__ import annotations
  import contextlib
  from typing import TYPE_CHECKING, Any, cast
  from docutils import nodes
  from docutils.nodes import Element, Node
  from sphinx import addnodes
  from sphinx.locale import __
  from sphinx.util import logging
  from sphinx.util.nodes import get_node_line
label_desc: Use image node_id 1 for calling a global function with example usage: _is_single_paragraph(node) and returns: False, False, True, False