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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 url2path(url):
 	""" 	If url identifies a file on the local host, return the path to the 	file otherwise raise ValueError. 	"""

	scheme, host, path, nul, nul, nul = urlparse(url)
	if scheme.lower() in ("", "file") and host.lower() in ("", "localhost"):
		return path
	raise ValueError(url)