<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def init(port=8813, numRetries=10, host="localhost", label="default"):
 """ Establish a connection to a TraCI-Server and store it under the given label. This method is not thread-safe. It accesses the connection pool concurrently. """

    _connections[label] = connect(port, numRetries, host)
    switch(label)
    return getVersion()