false)``` to switch to isolated position mode.
Futures_GateIO
GateIO futures exchange uses leverage value to set crossed position mode, and use exchange.SetMarginLevel(0) to switch to crossed position mode.
Futures_Bybit
Use exchange.IO("cross", true) to switch to full position mode, use exchange.IO("cross", false) to switch to position-by-position mode. Use exchange.IO("unified", true) to switch to unified margin interface, use exchange.IO("unified", false) to switch back to normal contract interface.