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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_dict(input_dict, search_key, search_value):

    '''
    Filters a dictionary of dictionaries by a key-value pair.

    :param input_dict:    is a dictionary whose values are lists of dictionaries
    :param search_key:    is the key in the leaf dictionaries
    :param search_values: is the value in the leaf dictionaries
    :return:              filtered dictionary
    '''

    output_dict = dict()

    for key, key_list in six.iteritems(input_dict):
        key_list_filtered = _filter_list(key_list, search_key, search_value)
        if key_list_filtered:
            output_dict[key] = key_list_filtered

    return output_dict