<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _or_query(self, term_list, field, field_type):
 """ Joins each item of term_list decorated by _term_query with an OR. """

        term_list = [self._term_query(term, field, field_type) for term in term_list]
        return xapian.Query(xapian.Query.OP_OR, term_list)