0.0.1

assembler.py从program.txt中读取汇编语言并进行汇编，再输入到machine_code_output.txt

只能简单的识别指令，不能识别标签等东西
注意嗷，阉割了伪指令功能

类似
jal r1, 0
jalr r1, r3, 6
addi r3, r1, 2
subi r4, r1, -2
beq r3, r4, -6
ble r3, r5, 0
add r5, r3, r4
sub r6, r3, r4
sb r5, 2(r6)
sw r5, 4(r6)
lb r7, 4(r6)
lw r8, 2(r6)
and r9, r5, r6
or r10, r5, r6
lui r11, 0xA1