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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 clean(self, elements):
		''' Removes empty or incomplete answers. '''

		cleanelements = []
		for i in xrange(len(elements)):
			if isempty(elements[i]):
				return []
			next = elements[i]
			if isinstance(elements[i], (list, tuple)):
				next = self.clean(elements[i])
			if next:
				cleanelements.append(elements[i])
		return cleanelements