if HL[m].str.contains('Mole_fraction_of') : AttributeError: 'str' object has no attribute 'str'

It seems that you are trying to use the `.str` method on a string object `HL[m]`. The `.str` method is used on Pandas Series or DataFrame objects to operate on each element of the series or dataframe as a string.

To fix this error, you need to check if `HL[m]` is a Pandas Series or DataFrame object before using the `.str` method. If it is a string object, you can use string methods such as `.split()` or `.startswith()` to manipulate the string.