docstr: It constructs the signature of the tuple value expression.
  It assumes the col_object attribute is populated by the binder with the catalog
  entries. For a standard column in the table, it returns `table_name.col_name`,
  and for function output columns it returns `function_name.col_name`
  Raises:
      ValueError: If the col_object is not a `Union[ColumnCatalogEntry, FunctionIOCatalogEntry]`. This can occur if the expression has not been bound using the binder.
  Returns:
      str: signature string
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code: def signature(self):
      """It constructs the signature of the tuple value expression.
      It assumes the col_object attribute is populated by the binder with the catalog
      entries. For a standard column in the table, it returns `table_name.col_name`,
      and for function output columns it returns `function_name.col_name`
      Raises:
          ValueError: If the col_object is not a `Union[ColumnCatalogEntry, FunctionIOCatalogEntry]`. This can occur if the expression has not been bound using the binder.
      Returns:
          str: signature string
      """
      assert isinstance(
          self.col_object, ColumnCatalogEntry
      ) or isinstance(
          self.col_object, FunctionIOCatalogEntry
      ), f"Unsupported type of self.col_object {type(self.col_object)}, expected ColumnCatalogEntry or FunctionIOCatalogEntry"
  
      col_name = self.col_object.name
      row_id = self.col_object.row_id
      if isinstance(self.col_object, ColumnCatalogEntry):
          return f"{self.col_object.table_name}.{col_name}[{row_id}]"
      elif isinstance(self.col_object, FunctionIOCatalogEntry):
          return f"{self.col_object.function_name}.{col_name}[{row_id}]"
  
imports: from typing import Union
  from evadb.catalog.models.column_catalog import ColumnCatalogEntry
  from evadb.catalog.models.function_io_catalog import FunctionIOCatalogEntry
  from evadb.models.storage.batch import Batch
  from .abstract_expression import AbstractExpression, ExpressionReturnType, ExpressionType
label_desc: Use image node_id 10 for calling the TupleValueExpression obj's underlying member method code with example usage: obj.signature() and returns: self, str, col_name, str, row_id, str, self, str, col_name, str, row_id, str