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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 _is_collinear(self, lons, lats):
 """ Checks if first three points are collinear - in the spherical case this corresponds to all points lying on a great circle and, hence, all coordinate vectors being in a single plane. """


        x, y, z = lonlat2xyz(lons[:3], lats[:3])
        pts = np.column_stack([x, y, z])

        collinearity = (np.linalg.det(pts.T) == 0.0)

        return collinearity