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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 step_indices(group_idx):
 """ Get the edges of areas within group_idx, which are filled with the same value """

    ilen = step_count(group_idx) + 1
    indices = np.empty(ilen, int)
    indices[0] = 0
    indices[-1] = group_idx.size
    inline(c_step_indices, ['group_idx', 'indices'], define_macros=c_macros, extra_compile_args=c_args)
    return indices