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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 copy_file(file_name):
 	""" 	Copy a given file from the cache storage 	"""


	remote_file_path = join(join(expanduser('~'), OCTOGRID_DIRECTORY), file_name)
	current_path = join(getcwd(), file_name)

	try:
		copyfile(remote_file_path, current_path)
	except Exception, e:
		raise e