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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 read_length_block(fp, fmt='I', padding=1):
 """ Read a block of data with a length marker at the beginning. :param fp: file-like :param fmt: format of the length marker :return: bytes object """

    length = read_fmt(fmt, fp)[0]
    data = fp.read(length)
    assert len(data) == length, (len(data), length)
    read_padding(fp, length, padding)
    return data