code: def _replace_numbers(content: str):
      """
      Replaces strings of the form <x> with circled unicode numbers (e.g. ①) as text.
  
      Args:
          content: Python str from a callout or annotations directive.
  
      Returns: The formatted content string.
      """
      for i in range(1, 20):
          content.replace(
              f"<{i}>", chr(int(f"0x{BASE_NUM + i}", base=16))
          )
      return content
  
imports: from docutils import nodes
  from sphinx.util.docutils import SphinxDirective
  from sphinx.transforms import SphinxTransform
  from docutils.nodes import Node
label_desc: Use image node_id 3 for calling a global function with example usage: _replace_numbers(content) and returns: content