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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 _feature_to_fields(f, jsonify=True):
 """ Convert feature to tuple, for faster sqlite3 import """

    x = []
    for k in constants._keys:
        v = getattr(f, k)
        if jsonify and (k in ('attributes', 'extra')):
            x.append(_jsonify(v))
        else:
            x.append(v)
    return tuple(x)