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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 _get_max_sigma(self, R):
 """Calculate maximum sigma of scanner RAS coordinates Parameters R : 2D array, with shape [n_voxel, n_dim] The coordinate matrix of fMRI data from one subject Returns ------- max_sigma : float The maximum sigma of scanner coordinates. """


        max_sigma = 2.0 * math.pow(np.nanmax(np.std(R, axis=0)), 2)
        return max_sigma