Unix Copying Whining

Why is it so wrong of me to want to copy files in the following way? (in iPython)

for item in to_save:
   ....:     try:
   ....:         folder = os.path.split(item)[0]
   ....:         os.makedirs("backup_folder/" + folder)
   ....:     except:
   ....:         pass
   ....:     !cp $item folder/$item

This would be ideal for me.

[The issue I'm complaining about is that when you copy a file in Unix, the target location must already exist for the file.  Python's os.makedirs() makes intermediary folders (unlike the similar os.makedir())--but, in neither Python nor Bash can I find a function that copies, while making those intermediary folders.  I can't imagine a danger in this, but seem to want to do it while backing up, all of the time.]