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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 get_value(haystack, needle, key_attribute="n", content_attribute="_content"):
 """ Fetch a value from a zimbra-like json dict (keys are "n", values are "_content" This function may be slightly faster than zimbra_to_python(haystack)[ needle], because it doesn't necessarily iterate over the complete list. :param haystack: The list in zimbra-dict format :param needle: the key to search for :return: the value or None, if the key is not found """


    for value in haystack:

        if value[key_attribute] == needle:

            return value[content_attribute]

    return None