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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 _instantiate(cls, params):
 """ Helper to instantiate Attention classes from parameters. Warns in log if parameter is not supported by class constructor. :param cls: Attention class. :param params: configuration parameters. :return: instance of `cls` type. """

    sig_params = inspect.signature(cls.__init__).parameters
    valid_params = dict()
    for key, value in params.items():
        if key in sig_params:
            valid_params[key] = value
        else:
            logger.debug('Type %s does not support parameter \'%s\'' % (cls.__name__, key))
    return cls(**valid_params)