Mark some output parsers as serializable (cross-checked w/ JS) (#7083)

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langchain/output_parsers/combining.py

@@ -10,6 +10,10 @@ from langchain.schema import BaseOutputParser
 class CombiningOutputParser(BaseOutputParser):
     """Class to combine multiple output parsers into one."""
 
+    @property
+    def lc_serializable(self) -> bool:
+        return True
+
     parsers: List[BaseOutputParser]
 
     @root_validator()

langchain/output_parsers/fix.py

@@ -13,6 +13,10 @@ T = TypeVar("T")
 class OutputFixingParser(BaseOutputParser[T]):
     """Wraps a parser and tries to fix parsing errors."""
 
+    @property
+    def lc_serializable(self) -> bool:
+        return True
+
     parser: BaseOutputParser[T]
     retry_chain: LLMChain
 

langchain/output_parsers/list.py

@@ -21,6 +21,10 @@ class ListOutputParser(BaseOutputParser):
 class CommaSeparatedListOutputParser(ListOutputParser):
     """Parse out comma separated lists."""
 
+    @property
+    def lc_serializable(self) -> bool:
+        return True
+
     def get_format_instructions(self) -> str:
         return (
             "Your response should be a list of comma separated values, "

langchain/output_parsers/regex.py

@@ -9,6 +9,10 @@ from langchain.schema import BaseOutputParser
 class RegexParser(BaseOutputParser):
     """Class to parse the output into a dictionary."""
 
+    @property
+    def lc_serializable(self) -> bool:
+        return True
+
     regex: str
     output_keys: List[str]
     default_output_key: Optional[str] = None