cursor.keys is None before calling cursor.stream()

[nicolewhite]

from neo4j.v1 import GraphDatabase

driver = GraphDatabase.driver("bolt://localhost")
session = driver.session()
tx = session.begin_transaction()
cursor = tx.run("MATCH (n:Person) RETURN n.name, n.born LIMIT 5;")

print(cursor.keys)

for row in cursor.stream():
    print({"keys": row.keys(), "values": row.values()})

print(cursor.keys)

None
{'keys': (u'n.name', u'n.born'), 'values': (u'Keanu Reeves', 1964)}
{'keys': (u'n.name', u'n.born'), 'values': (u'Carrie-Anne Moss', 1967)}
{'keys': (u'n.name', u'n.born'), 'values': (u'Laurence Fishburne', 1961)}
{'keys': (u'n.name', u'n.born'), 'values': (u'Hugo Weaving', 1960)}
{'keys': (u'n.name', u'n.born'), 'values': (u'Andy Wachowski', 1967)}
[u'n.name', u'n.born']