class_docstr: Return the length of ``ls``.
  
  Parameters
  ----------
  ls: List[*] (Required)
  
  Returns
  -------
  <i32>
      * Length of ``ls``.
  
  Attributes
  ----------
  T: fp16, fp32, i32, bool
class_docstr_tok: ["Return","the","length","of","``","ls","``",".","Parameters","--","--","--","--","--","ls",":","List","[","*","]","(","Required",")","Returns","--","--","--","-","<","i32",">","*","Length","of","``","ls","``",".","Attributes","--","--","--","--","--","T",":","fp16",",","fp32",",","i32",",","bool"]
code: def type_inference(self):
      return types.int32
  
imports: import copy
  import numpy
  from coremltools import _logger
  from coremltools.converters.mil.mil import Block, get_existing_symbol, get_new_symbol, types
  from coremltools.converters.mil.mil.input_type import DefaultInputs, InputSpec, InternalInputType, ListInputType, PyFunctionInputType, TensorInputType, TupleInputType
  from coremltools.converters.mil.mil.operation import NONE, SYMBOL, VALUE, Operation, mil_list, precondition
  from coremltools.converters.mil.mil.ops.defs._op_reqs import register_op
  from coremltools.converters.mil.mil.ops.defs._utils import infer_type_with_broadcast, promoted_primitive_type
  from coremltools.converters.mil.mil.types import is_compatible_type
  from coremltools.converters.mil.mil.types.type_list import list
  from coremltools.converters.mil.mil.types.type_mapping import builtin_to_string, is_subtype, numpy_type_to_builtin_type, numpy_val_to_builtin_val
label_desc: Use image node_id 1 for calling the list_length obj's underlying member method code with example usage: obj.type_inference() and returns: types