I have a dataframe df that looks like the following:
Type      Size
Biomass   12
Coal      15
Nuclear   23
And I have a string str such as the following: Biomass_wood
I would like to return the following dataframe:
Type      Size
Biomass   12
This is because Biomass is partially matched by the first part of Biomass_wood.
This would effectively be the opposite of df[df.Type.str.contains(str)] as the bigger string is contained in str and not in the column Type
 
    