polars.Expr.deserialize#

classmethod Expr.deserialize(source: str | Path | IOBase) Self[source]#

Read a serialized expression from a file.

Parameters:
source

Path to a file or a file-like object (by file-like object, we refer to objects that have a read() method, such as a file handler (e.g. via builtin open function) or BytesIO).

Warning

This function uses pickle when the logical plan contains Python UDFs, and as such inherits the security implications. Deserializing can execute arbitrary code, so it should only be attempted on trusted data.

Examples

>>> from io import StringIO
>>> expr = pl.col("foo").sum().over("bar")
>>> json = expr.meta.serialize()
>>> pl.Expr.deserialize(StringIO(json))
<Expr ['col("foo").sum().over([col("ba…'] at ...>