class_docstr: Utility class for the `when-then-otherwise` expression.
  
  Represents the initial state of the expression after `pl.when(...)` is called.
  
  In this state, `then` must be called to continue to finish the expression.
class_docstr_tok: ["Utility","class","for","the","`","when-then-otherwise","`","expression",".","Represents","the","initial","state","of","the","expression","after","`","pl.when","(","...",")","`","is","called",".","In","this","state",",","`","then","`","must","be","called","to","continue","to","finish","the","expression","."]
code: def __init__(self, when: Any):
      self._when = when
  
imports: from __future__ import annotations
  from typing import TYPE_CHECKING, Any, Iterable
  import polars.functions
  from polars.expr.expr import Expr
  from polars.utils._parse_expr_input import parse_as_expression, parse_when_constraint_expressions
  from polars.utils._wrap import wrap_expr
label_desc: Use image node_id 1 to create a new When object  with example: obj = When(when)