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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_where_clause_from_dict(dictionary, join_operator='AND'):
 """Builds a where clause from a dictionary """

        CoyoteDb.escape_dictionary(dictionary)
        clause = join_operator.join(
            (' {k} is {v} ' if str(v).lower() == 'null' else ' {k} = {v} ').format(k=k, v=v)  # IS should be the operator for null values
            for k, v in dictionary.iteritems())
        return clause