class_docstr: List of clauses container.
class_docstr_tok: ["List","of","clauses","container","."]
code: def __str__(self) -> str:
      clauses = list(self._flatten())
      if not clauses:
          return ""
      elif len(clauses) == 1:
          return str(clauses[0])
      else:
          return f" {self.separator} ".join(
              f"({clause})" for clause in clauses
          )
  
file_path: tfx/tfx/orchestration/portable/mlmd/filter_query_builder.py
imports: import collections
  from typing import Any, List, Sequence, Union
  import ml_metadata
label_desc: Use image node_id 2 for calling the _ClauseList obj's underlying member method code with example usage: obj.__str__() and returns: str, str, str, self, str