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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 wildcard_allowed_principals(self, pattern=None):
 """ Find statements which allow wildcard principals. A pattern can be specified for the wildcard principal """


        wildcard_allowed = []

        for statement in self.statements:
            if statement.wildcard_principals(pattern) and statement.effect == "Allow":
                wildcard_allowed.append(statement)

        return wildcard_allowed