title: Move file after Pipeline has run
body: <p>Is it possible to move a file in GCS after the dataflow pipeline has finished running? If so, how? Should be the last <code>.apply</code>? I can't imagine that being the case. </p>
  
  <p>The case here is that we are importing a lot of .csv's from a client. We need to keep those CSV's indefinitely, so we either need to "mark the CSV as being already handled", or alternatively, move them out of the initial folder that <code>TextIO</code> uses to find the csv's. The only thing I can currently think of is storing the file name (I'm not sure how I'd get this even, I'm a DF newbie) in BigQuery perhaps, and then excluding files that have already been stored from the execution pipeline somehow? But there has to be a better approach. </p>
  
  <p>Is this possible? What should I check out? </p>
  
  <p>Thanks for any help!</p>