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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 add_dict_to_hash(a_hash, a_dict):
 """Adds `a_dict` to `a_hash` Args: a_hash (`Hash`):
 the secure hash, e.g created by hashlib.md5 a_dict (dict[string, [string]]):
 the dictionary to add to the hash """

    if a_dict is None:
        return
    for k, v in a_dict.items():
        a_hash.update(b'\x00' + k.encode('utf-8') + b'\x00' + v.encode('utf-8'))