Method _copy

lib/sqlalchemy/sql/schema.py:4805–4835

(
        self,
        *,
        target_table: Optional[Table] = None,
        **kw: Any,
    )

        return self._copy(target_table=target_table, **kw)

    def _copy(
        self,
        *,
        target_table: Optional[Table] = None,
        **kw: Any,
    ) -> ColumnCollectionConstraint:
        # ticket #5276
        constraint_kwargs = {}
        for dialect_name in self.dialect_options:
            dialect_options = self.dialect_options[dialect_name]._non_defaults
            for (
                dialect_option_key,
                dialect_option_value,
            ) in dialect_options.items():
                constraint_kwargs[dialect_name + "_" + dialect_option_key] = (
                    dialect_option_value
                )

        assert isinstance(self.parent, Table)
        c = self.__class__(
            name=self.name,
            deferrable=self.deferrable,
            initially=self.initially,
            *[
                _copy_expression(expr, self.parent, target_table)
                for expr in self._columns
            ],
            comment=self.comment,
            **constraint_kwargs,
        )
        return self._schema_item_copy(c)

    def contains_column(self, col: Column[Any]) -> bool:
        """Return True if this constraint contains the given column.