<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1"> </head> <body text="#000000" bgcolor="#ffffff"> Dear sir, Since several days, I'm trying to post an answer to a question I asked. I always have the following message : Pending Alert: This post has NOT been accepted by the mailing list yet. I have subscribed once, then I have re-subscribed, and one more time and ... I have been said several times that I am well registered.  I have posted through the web site, through this mailing. Nothing is doing. So I don't know what to do. Please tell me exactly what to do. Best regards. Pierre. Following is my answer to the qustion : Thank tim-Philipp for this reply. I already inspect the link you gave me, but  (may be I don't understand) I do not find in which library are the described functions shown in this document. Unfortunately, I have not time enough to contribute to an existing project. More of that I don't know the Python . language use for the Pitivi project. Thank's for your help. Pierre </body> </html>