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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 copy_keys(source, destination, keys=None):
 """ Add keys in source to destination Parameters source : dict destination: dict keys : None | iterable The keys in source to be copied into destination. If None, then `keys = destination.keys()` """

    if keys is None:
        keys = destination.keys()
    for k in set(source) & set(keys):
        destination[k] = source[k]
    return destination