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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 apply_mapping(raw_row, mapping):
    '''
    Override this to hand craft conversion of row.
    '''
    row = {target: mapping_func(raw_row[source_key])
           for target, (mapping_func, source_key)
           in mapping.fget().items()}
    return row