class_docstr: an OpenType subtable (%s) had a format I didn't expect
code: def __init__(self, merger=None, **kwargs):
      super().__init__(merger, **kwargs)
      if not self.stack:
          self.stack = [".Format"]
  
imports: import textwrap
label_desc: Use image node_id 1 to create a new UnsupportedFormat object from inherited base classes: VarLibMergeError with example: obj = UnsupportedFormat(merger)