attributeerror dataframe object has dataframe object has no attribute str solve the attributeerror str object dataframe object has no attribute str str object has no attribute append attribute error str object has no python attributeerror str object has dataframe object has no attribute str python attributeerror str object has dataframe object has no attribute sort nonetype object has no attribute module string has no attribute lower str object has no attribute read dataframe object has no attribute str attributeerror dataframe object has pandas datetimeproperties object has str object has no attribute values str object has no attribute decode python attributeerror str object has attributeerror dataframe object has str object has no attribute append python attributeerror list object dict object has no attribute append attributeerror dataframe object module string has no attribute lower attributeerror dataframe object has attributeerror str object has no str object has no attribute splt と 10 common pandas errors and how to fix knime python script none type object str replace python dataframe object has no