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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 delete_all(self, criteria: Q = None):
 """Delete the dictionary object by its criteria"""

        if criteria:
            # Delete the object from the dictionary and return the deletion count
            items = self._filter(criteria, self.conn['data'][self.schema_name])

            # Delete all the matching identifiers
            with self.conn['lock']:
                for identifier in items:
                    self.conn['data'][self.schema_name].pop(identifier, None)

            return len(items)
        else:
            with self.conn['lock']:
                if self.schema_name in self.conn['data']:
                    del self.conn['data'][self.schema_name]