I’m cleaning an amazon dataframe with reviewers.I have duplicates in the reviewerID column because some users left several reviews. However, in the reviewerName column, I have both NaN values and names for the same reviewer. How can I drop NaN values in the reviewerName column for duplicated reviewers and leave only names?
Reviewers dataframe
I tried to use np.where to replace NaN values with names (I wanted to drop duplicates after the replacement), but I got an error message: unsupported operand type(s) for &: ‘str’ and ‘bool’

reviewers = np.where(((reviewers[reviewers.duplicated('reviewerID', keep=False) == True])&(reviewers['reviewerName']==reviewers['reviewerName'].isna())),((reviewers[reviewers.duplicated('reviewerID', keep=False) == True])&(reviewers['reviewerName']!=reviewers['reviewerName'].isna())), ((reviewers[reviewers.duplicated('reviewerID', keep=False) == True])&(reviewers['reviewerName']!=reviewers['reviewerName'].isna())))

Thank you in advance for your help!