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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_full(data, size):
 """ read_full reads exactly `size` bytes from reader. returns `size` bytes. :param data: Input stream to read from. :param size: Number of bytes to read from `data`. :return: Returns :bytes:`part_data` """

    default_read_size = 32768 # 32KiB per read operation.
    chunk = io.BytesIO()
    chunk_size = 0

    while chunk_size < size:
        read_size = default_read_size
        if (size - chunk_size) < default_read_size:
            read_size = size - chunk_size
        current_data = data.read(read_size)
        if not current_data or len(current_data) == 0:
            break
        chunk.write(current_data)
        chunk_size+= len(current_data)

    return chunk.getvalue()