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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 start(grains=False, grain_keys=None, pillar=False, pillar_keys=None):
    '''
    Execute the Thorium runtime
    '''
    state = salt.thorium.ThorState(
            __opts__,
            grains,
            grain_keys,
            pillar,
            pillar_keys)
    state.start_runtime()