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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 update_with_tohu_generators(field_gens, adict):
 """ Helper function which updates `field_gens` with any items in the dictionary `adict` that are instances of `TohuUltraBaseGenerator`. """

    for name, gen in adict.items():
        if isinstance(gen, TohuUltraBaseGenerator):
            field_gens[name] = gen