code: def __getitem__(self, item):
      def safe_collect():
          res = None
          if self.proxy_cache is not None:
              res = self.proxy_cache.get(key)
          if not res:
              try:
                  res = self.meta_run_attrs_tree.collect(key)
              except Exception:
                  res = SafeNone()
              if self.proxy_cache is not None:
                  self.proxy_cache[key] = res
          return res
  
      if isinstance(item, str):
          metric_name = item
          context_idx = Context({}).idx
      elif isinstance(item, tuple):
          if len(item) > 2:
              return SafeNone()
          metric_name, context = item
          if not isinstance(metric_name, str):
              return SafeNone()
          if isinstance(context, int):
              context_idx = context
          elif isinstance(context, dict):
              context_idx = Context(context).idx
          else:
              return SafeNone()
      else:
          return SafeNone()
  
      key = ("traces", context_idx, metric_name)
      return AimObjectProxy(
          safe_collect,
          view=self.meta_run_tree.subtree(key),
          cache=self.proxy_cache,
      )
  
imports: import datetime
  import pytz
  from typing import Any, Union
  from typing import TYPE_CHECKING
  from aim.storage.context import Context
  from aim.storage.proxy import AimObjectProxy
  from aim.storage.structured.entities import StructuredObject
  from aim.storage.treeview import TreeView
  from aim.storage.types import AimObject, AimObjectKey, AimObjectPath, SafeNone
  from aim.storage.structured.sql_engine.entities import ModelMappedRun
label_desc: Use image node_id 2 for calling the MetricsView obj's underlying member method code with example usage: obj.__getitem__(item) and returns: AimObjectProxy, res, SafeNone, SafeNone, SafeNone, SafeNone