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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def upload(ui, repo, name, **opts):
 	"""upload diffs to the code review server 	Uploads the current modifications for a given change to the server. 	"""

	if codereview_disabled:
		raise hg_util.Abort(codereview_disabled)

	repo.ui.quiet = True
	cl, err = LoadCL(ui, repo, name, web=True)
	if err != "":
		raise hg_util.Abort(err)
	if not cl.local:
		raise hg_util.Abort("cannot upload non-local change")
	cl.Upload(ui, repo)
	print "%s%s\n" % (server_url_base, cl.name)
	return 0