code: def digraph_edge(*, tail: str, head: str, attr: str) -> str:
      """Return DOT digraph edge statement line."""
      return f"\t{tail} -> {head}{attr}\n"
  
imports: import contextlib
  import typing
  from .None import _tools
  from .None import base
  from .None import quoting
label_desc: Use image node_id 5 for calling a global function with example usage: digraph_edge() and returns: str, tail, str, head, attr, str