#NEWLINE# def match_one( self , start_node = None , rel_type = None , end_node = None , bidirectional = False ) : #NEWLINE# #INDENT# ' Match and return one relationship with specific criteria.\n\n        :param start_node: start node of relationships to match (:const:`None` means any node)\n        :param rel_type: type of relationships to match (:const:`None` means any type)\n        :param end_node: end node of relationships to match (:const:`None` means any node)\n        :param bidirectional: :const:`True` if reversed relationships should also be included\n        ' #NEWLINE# rels = list ( self . match ( start_node , rel_type , bidirectional , bidirectional , 1 ) ) #NEWLINE# if rels : #NEWLINE# #INDENT# return rels [ 0 ] #NEWLINE# #UNINDENT# else : #NEWLINE# #INDENT# return None