code: def __str__(self):
      return f"matrix {{global: {self.global_type}, col: {self.col_type}, col_key: {self._col_key_str()}, row: {self.row_type}, row_key: [{self._row_key_str()}], entry: {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 10 for calling the tmatrix obj's underlying member method code with example usage: obj.__str__() and returns: str, self, str, self, str, self, str, self, str, self, str, self, str