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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 group_pairs(blocks, layout_blocks_list):
 """Sort a list of layout blocks into pairs Arguments: List:blocks -- List of block objects List:layout_blocks -- List of layout block indexes Returns: List -- Layout block pair indexes grouped in a list """


    image_dict={}
    for block_id in layout_blocks_list:
        image_seq=blocks[block_id].ec_hdr.image_seq
        if image_seq not in image_dict:
            image_dict[image_seq]=[block_id]
        else:
            image_dict[image_seq].append(block_id)

    log(group_pairs, 'Layout blocks found at PEBs: %s' % list(image_dict.values()))

    return list(image_dict.values())