I am exactly doing the same thing
when running I am getting following output
Didn’t find op for builtin opcode ‘DEPTHWISE_CONV_2D’ version ‘3’
Failed to get registration from op code  d
AllocateTensors() failed
Guru Meditation Error: Core  1 panic’ed (LoadProhibited). Exception was unhandled.
Core  1 register dump:
PC      : 0x400d2890  PS      : 0x00060d30  A0      : 0x800daa57  A1      : 0x3ffb2800
A2      : 0x3ffd3efc  A3      : 0x00000000  A4      : 0x3ffc16e0  A5      : 0x3ffc1638
A6      : 0x3ffc1640  A7      : 0x00000001  A8      : 0x800d2851  A9      : 0x3ffb27b0
A10     : 0x00000000  A11     : 0x00000060  A12     : 0x00000060  A13     : 0x00000001
A14     : 0x00011800  A15     : 0x3ffc1640  SAR     : 0x00000006  EXCCAUSE: 0x0000001c
EXCVADDR: 0x00000004  LBEG    : 0x40089029  LEND    : 0x40089039  LCOUNT  : 0xffffffff
Backtrace:0x400d288d:0x3ffb28000x400daa54:0x3ffb2820
ELF file SHA256: 0000000000000000
Rebooting…