[Python] RuntimeError in DolphinDB Python SDK: Connection closed when reusing ddb.session -...

I’m using the DolphinDB Python SDK and encountering connection issues when working with

class methods. Here’s a simplified version of my code:

class DBHandler:
def connect_ddb(self):
conn = ddb.session()
conn.connect("xxx") # Host/port details
return conn

def funcA(self):
conn = self.connect_ddb()
conn.run("some_query")


# Usage
handler = DBHandler()
for _ in range(100):
handler.funcA() # Works initially but fails after several iterations


The error occurs after some time of frequent usage:

RuntimeError: <Exception> in run: Couldn't send script/function to the remote host because the connection has been closed


I’m wondering what might be causing this issue. Is it because the connection established by ddb.session times out after a certain period? Or could there be other reasons? How can I fix this problem to ensure that the connection remains stable and the run method can be executed without errors?

My environment:

• DolphinDB Python API version: 3.0.2.3
• DolphinDB server version: 3.00.2.5
• Python version: 3.9.2rc1

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