code: def to_dict(self):
      return dict(
          global_type=str(self.global_type),
          col_type=str(self.col_type),
          col_key=self.col_key,
          row_type=str(self.row_type),
          row_key=self.row_key,
          entry_type=self.entry_type,
      )
  
imports: import pprint
  from hail.typecheck import typecheck_method, sequenceof
  from hail.utils.java import escape_parsable
  from hail.expr.types import dtype, tstruct
  from hail.utils.java import jiterable_to_list
label_desc: Use image node_id 4 for calling the tmatrix obj's underlying member method code with example usage: obj.to_dict() and returns: dict