class_docstr: Represents a slice with a dynamic start index and a fixed size.
code: def from_slice(cls, slc: slice, size: int) -> Slice:
      start, stop, step = slc.indices(size)
      if step != 1:
          raise ValueError(
              f"slice must have a step of 1 (found: {step})"
          )
      return cls(start, stop - start)
  
imports: from __future__ import annotations
  import dataclasses
  from typing import Any, Union
  from jax._src import core
  from jax._src import tree_util
  from jax._src.typing import Array
  from jax._src.util import merge_lists
  from jax._src.util import partition_list
  import numpy
label_desc: Use image node_id 4 for calling the Slice obj's underlying member method code with example usage: obj.from_slice(cls, slc, size) and returns: cls