According to Robin Dunn, at least one FTP server returns 200 instead

gvanrossum · gvanrossum · commit 6bbd1d0f0efc · 1998-07-02T20:41:20.000Z
of 250 on a successful delete.
diff --git a/Lib/ftplib.py b/Lib/ftplib.py
@@ -422,7 +422,7 @@ def rename(self, fromname, toname):
 	def delete(self, filename):
 		'''Delete a file.'''
 		resp = self.sendcmd('DELE ' + filename)
-		if resp[:3] == '250':
+		if resp[:3] in ('250', '200'):
 			return resp
 		elif resp[:1] == '5':
 			raise error_perm, resp
