I have daily data in string format as 1/1/ 2019. The string length is different as there as values e.g. 1/1/2019, 1/23/2019, 12/31/2019, 2/1/2020, 2/29/2020 etc. I need to get it into a monthly numeric data as 20190724, 20200313 etc. I could not mange it with the 'datetime' method. Any help in this regard?