class_docstr: A collection of parameters, metrics, and artifacts to create a ML model.
class_docstr_tok: ["A","collection","of","parameters",",","metrics",",","and","artifacts","to","create","a","ML","model","."]
docstr: Updates the start time of the run.
  
  Returns:
      object: self.
docstr_tok: ["Updates","the","start","time","of","the","run",".","Returns",":","object",":","self","."]
code: def __enter__(self):
      """Updates the start time of the run.
  
      Returns:
          object: self.
      """
      nested_with_err_msg_template = (
          "It is not allowed to use nested 'with' statements on the {}."
      )
      if self._in_load:
          if self._inside_load_context:
              raise RuntimeError(
                  nested_with_err_msg_template.format("load_run")
              )
          self._inside_load_context = True
          if not self._inside_init_context:
              # Add to run context only if the load_run is called separately
              # without under a Run init context
              _RunContext.add_run_object(self)
      else:
          if _RunContext.get_current_run():
              raise RuntimeError(
                  nested_with_err_msg_template.format("Run")
              )
          self._inside_init_context = True
          _RunContext.add_run_object(self)
  
      if not self._trial_component.start_time:
          start_time = datetime.datetime.now(dateutil.tz.tzlocal())
          self._trial_component.start_time = start_time
      self._trial_component.status = _api_types.TrialComponentStatus(
          primary_status=_TrialComponentStatusType.InProgress.value,
          message="Within a run context",
      )
      # Save the start_time and status changes to backend
      self._trial_component.save()
      return self
  
imports: from __future__ import absolute_import
  import datetime
  import logging
  from enum import Enum
  from math import isnan, isinf
  from numbers import Number
  from typing import Optional, List, Dict, TYPE_CHECKING, Union
  import dateutil
  from numpy import array
  from sagemaker.apiutils import _utils
  from sagemaker.experiments import _api_types
  from sagemaker.experiments._api_types import TrialComponentArtifact, _TrialComponentStatusType
  from sagemaker.experiments._helper import _ArtifactUploader, _LineageArtifactTracker, _DEFAULT_ARTIFACT_PREFIX
  from sagemaker.experiments._environment import _RunEnvironment
  from sagemaker.experiments._run_context import _RunContext
  from sagemaker.experiments.experiment import Experiment
  from sagemaker.experiments._metrics import _MetricsManager
  from sagemaker.experiments.trial import _Trial
  from sagemaker.experiments.trial_component import _TrialComponent
  from sagemaker.utils import get_module, unique_name_from_base, format_tags, Tags, TagsDict
  from sagemaker.experiments._utils import guess_media_type, resolve_artifact_name, verify_length_of_true_and_predicted, validate_invoked_inside_run_context, get_tc_and_exp_config_from_job_env, verify_load_input_names, is_run_trial_component
label_desc: Use image node_id 19 for calling the Run obj's underlying member method code with example usage: obj.__enter__() and returns: self