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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 count(self, item):
 """Counts references to 'item' in a caseless manner. If item is not a string it will always return 0."""

        if not isinstance(item, str):
            return 0
        count = 0
        for entry in self:
            if item.lower() == entry.lower():
                count += 1
        return count