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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 merge(a, b):
    "merges b into a recursively if a and b are dicts"
    for key in b:
        if isinstance(a.get(key), dict) and isinstance(b.get(key), dict):
            merge(a[key], b[key])
        else:
            a[key] = b[key]
    return a