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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 build_where_clause(mappings, operator='AND'):
 """Constructs the where clause based on a dictionary of values """

        where_clause_mappings = {}
        where_clause_mappings.update(mappings)

        where_clause = 'WHERE ' + ' {} '.format(operator).join(
            '{k} = {v}'.format(k=k, v='"{}"'.format(v) if isinstance(v, basestring) else v)
            for k, v in where_clause_mappings.iteritems()
        )
        return where_clause