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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 _filter_settings(settings, prefix):
 """ Filter all settings to only return settings that start with a certain prefix. :param dict settings: A settings dictionary. :param str prefix: A prefix. """

    ret = {}
    for skey in settings.keys():
        if skey.startswith(prefix):
            key = skey[len(prefix):]
            ret[key] = settings[skey]
    return ret