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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 get_deprecated_gene_ids(filename):
 """ gets a dict of the gene IDs used during in DDD datasets that have been deprecated in favour of other gene IDs """

    
    deprecated = {}
    with open(filename) as handle:
        for line in handle:
            line = line.strip().split()
            old = line[0]
            new = line[1]
            deprecated[old] = new
    
    return deprecated