How to ignore case in dataframe groupby?

[Bharathi Raja]

Hi,
Values in a dataframe column named countrycode are in different cases. Eg: (US, 
us).  groupBy & count gives two rows but the requirement is to ignore case for 
this operation.
1) Is there a way to ignore case in groupBy? Or
2) Is there a way to update the dataframe column countrycode to uppercase?

Thanks in advance.

Regards,
Raja