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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 dict_deep_merge(a, b, path=None):
 """Deep-merge dictionary `b` into dictionary `a`. Kudos to http://stackoverflow.com/a/7205107/145400 """

    if path is None:
        path = []
    for key in b:
        if key in a:
            if isinstance(a[key], dict) and isinstance(b[key], dict):
                dict_deep_merge(a[key], b[key], path + [str(key)])
            elif a[key] == b[key]:
                # Key conflict, but equal value.
                pass
            else:
                # Key/value conflict. Prioritize b over a.
                a[key] = b[key]
        else:
            a[key] = b[key]
    return a