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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 is_active(self, instance, conditions):
 """ Given an instance, and the conditions active for this switch, returns a boolean representing if the feature is active. """

        return_value = None
        for name, field in self.fields.iteritems():
            field_conditions = conditions.get(self.get_namespace(), {}).get(name)
            if field_conditions:
                value = self.get_field_value(instance, name)
                for status, condition in field_conditions:
                    exclude = status == EXCLUDE
                    if field.is_active(condition, value):
                        if exclude:
                            return False
                        return_value = True
                    else:
                        if exclude:
                            return_value = True
        return return_value