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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 decode_keys(store, encoding='utf-8'):
 """ If a dictionary has keys that are bytes decode them to a str. Parameters --------- store : dict Dictionary with data Returns --------- result : dict Values are untouched but keys that were bytes are converted to ASCII strings. Example In [1]: d Out[1]: {1020: 'nah', b'hi': 'stuff'} In [2]: trimesh.util.decode_keys(d) Out[2]: {1020: 'nah', 'hi': 'stuff'} """

    keys = store.keys()
    for key in keys:
        if hasattr(key, 'decode'):
            decoded = key.decode(encoding)
            if key != decoded:
                store[key.decode(encoding)] = store[key]
                store.pop(key)
    return store