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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 filter(self, filter):
 """Filter entries by calling function or applying regex."""

        if hasattr(filter, '__call__'):
            return [entry for entry in self.entries if filter(entry)]
        else:
            pattern = re.compile(filter, re.IGNORECASE)
            return [entry for entry in self.entries if pattern.match(entry)]