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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 _validate_number_of_layers(self, number_of_layers):
 """ Makes sure that the specified number of layers to squash is a valid number """


        # Only positive numbers are correct
        if number_of_layers <= 0:
            raise SquashError(
                "Number of layers to squash cannot be less or equal 0, provided: %s" % number_of_layers)

        # Do not squash if provided number of layer to squash is bigger
        # than number of actual layers in the image
        if number_of_layers > len(self.old_image_layers):
            raise SquashError(
                "Cannot squash %s layers, the %s image contains only %s layers" % (number_of_layers, self.image, len(self.old_image_layers)))