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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 gaussian_filter(self, sigma=2, order=0):
 """ Spatially smooth images with a gaussian filter. Filtering will be applied to every image in the collection. Parameters sigma : scalar or sequence of scalars, default = 2 Size of the filter size as standard deviation in pixels. A sequence is interpreted as the standard deviation for each axis. A single scalar is applied equally to all axes. order : choice of 0 / 1 / 2 / 3 or sequence from same set, optional, default = 0 Order of the gaussian kernel, 0 is a gaussian, higher numbers correspond to derivatives of a gaussian. """

        from scipy.ndimage.filters import gaussian_filter

        return self.map(lambda v: gaussian_filter(v, sigma, order), value_shape=self.value_shape)