Python - convert date string from YYYY-MM-DD to DD-MMM-YYYY using datetime?

Question

So I have read a number of threads on this, and am still stumped. Any help would be sincerely appreciated.

I have a column in a dataframe that contains strings of dates,

Answer 1

No need apply by using pd.to_datetime

pd.to_datetime(df_combined['VisitDate'],errors='coerce',format='%d-%b-%Y').fillna('')

Answer 2

You probably just need to assign the result back to the column itself:

df_combined['VisitDate'] = df_combined['VisitDate'].apply(lambda x: datetime.datetime.strptime(x, '%Y-%m-%d').strftime('%d-%b-%Y') if x != "" else "")