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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 by_image_seq(blocks, image_seq):
 """Filter blocks to return only those associated with the provided image_seq number. Argument: List:blocks -- List of block objects to sort. Int:image_seq -- image_seq number found in ec_hdr. Returns: List -- List of block indexes matching image_seq number. """

    return list(filter(lambda block: blocks[block].ec_hdr.image_seq == image_seq, blocks))