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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 simple_merge(kls, skeletons):
 """ Simple concatenation of skeletons into one object without adding edges between them. """

    if len(skeletons) == 0:
      return PrecomputedSkeleton()

    if type(skeletons[0]) is np.ndarray:
      skeletons = [ skeletons ]

    ct = 0
    edges = []
    for skel in skeletons:
      edge = skel.edges + ct
      edges.append(edge)
      ct += skel.vertices.shape[0]

    return PrecomputedSkeleton(
      vertices=np.concatenate([ skel.vertices for skel in skeletons ], axis=0),
      edges=np.concatenate(edges, axis=0),
      radii=np.concatenate([ skel.radii for skel in skeletons ], axis=0),
      vertex_types=np.concatenate([ skel.vertex_types for skel in skeletons ], axis=0),
      segid=skeletons[0].id,
    )