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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 context(type_config='float', **kw):
 """CPU Context."""

    backends = ['cpu:float']
    if type_config == 'half':
        backends = ['cpu:half', 'cpu:float']
    elif type_config == 'float':
        pass
    else:
        raise ValueError("Unknown data type config is given %s" % type_config)
    return nn.Context(backends, array_classes()[0], '')