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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 split_pem(s):
 """ Split PEM objects. Useful to process concatenated certificates. """

    pem_strings = []
    while s != b"":
        start_idx = s.find(b"-----BEGIN")
        if start_idx == -1:
            break
        end_idx = s.find(b"-----END")
        end_idx = s.find(b"\n", end_idx) + 1
        pem_strings.append(s[start_idx:end_idx])
        s = s[end_idx:]
    return pem_strings