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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 sort_prefixes(orig, prefixes='@+'):
 """Returns a sorted list of prefixes. Args: orig (str):
 Unsorted list of prefixes. prefixes (str):
 List of prefixes, from highest-priv to lowest. """

    new = ''
    for prefix in prefixes:
        if prefix in orig:
            new += prefix
    return new