code: def __post_init__(self):
      if self.units in ("pts", "points", "px", "pixels"):
          self.units = "pt"
      elif self.units in ("in", "inch", "inches"):
          self.units = "in"
      elif self.units in ("line", "lines"):
          self.units = "lines"
  
imports: from __future__ import annotations
  from dataclasses import dataclass
  from typing import TYPE_CHECKING
label_desc: Use image node_id 1 for calling the Margin obj's underlying member method code with example usage: obj.__post_init__() without return types