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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, name):
        '''Filter out problematic characters.

        This should become a separate module allowing the user to define filter rules
        from a bootstrap file and most likely become a separate module.
        '''

        name = name.replace("'", '')
        name = name.replace('"', '')
        name = name.replace('!(null)', '')
        name = name.replace(" ", "_")
        name = name.replace("/", "_")
        name = name.replace(".", "_")
        return name.lower()