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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 dictionary_merge(a, b):
 """merges dictionary b into a Like dict.update, but recursive """

    for key, value in b.items():
        if key in a and isinstance(a[key], dict) and isinstance(value, dict):
            dictionary_merge(a[key], b[key])
            continue
        a[key] = b[key]
    return a