code: def dataframe_warn_indexname(trait, value):
      if value.index.name is not None:
          warnings.warn(
              "The '%s' dataframe trait of the %s instance disregards the index name"
              % (trait.name, trait.this_class)
          )
          value = value.reset_index()
      return value
  
imports: from traitlets import TraitError, TraitType
  import numpy
  import pandas
  import warnings
  import datetime
  import six
label_desc: Use image node_id 11 for calling a global function with example usage: dataframe_warn_indexname(trait, value) and returns: value