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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 _parse_filter_string(filter_string):
 """ parse a filter string into a key-value pair """

    assert "=" in filter_string, "filter string requires an '=', got {0}".format(filter_string)
    split_values = filter_string.split('=')
    assert len(split_values) == 2, "more than one equals found in filter string {0}!".format(filter_string)
    return split_values