This is one of my STM32 boards, the Terminus 2, using the STM32F405ZGT6
External power is 12 VDC supplied via barrel or Molex connector. The Molex connector exposes a number of ADC, USART, GPIO and CAN interfaces. The board includes a MicroSD card slot, USB and RS232 connectivity.
Some of the Telit modems support Python internally, we have Micro Python ported on to the F4 platform. Board come with a boot loader permitting interaction with the modem and execution of application code.
Full JTAG/SWD connectivity with SWV support, and BOOT0 jumper.
HE910 GSM Plug-In Module
LE910 LTE Plug-In Module
I also have Arduino Shield adapters to get the modems onto NUCLEO or DISCO board configurations. The higher current requirements exceed USB specification, so I power the NUCLEO's with an external 7 VDC supply on the VIN side.