预期缩进的块错误<python>

Question

I'm making ARM processor, but error occured at unexpected part!:( I know about using tab, but I don't know about what is wrong. please help me!!!

def LDSTR():
    global k
    I=memory[k]/0b10000000000000000000000000%0b10
    P=memory[k]/0b1000000000000000000000000%0b10
    B=memory[k]/0b10000000000000000000000%0b10
    W=memory[k]/0b1000000000000000000000%0b10
    L=memory[k]/0b100000000000000000000%0b10
    if(I==0):
        if(P==0):
            #add offset after transfer (example) ldr Rx,[Ry],Rz
            if(B==0):
                #ldr/str word (example) ldr Rx,Ry
                if(W==0):
                    #no '!'
                    if(L==0):   
                        #str Rx,[Ry],Rz
                    elif(L==1):                     >>>error occured!!
                        #ldr Rx,[Ry],Rz
                elif(W==1):
                    #'!'exists (example)ldr Rx,[Ry,Rz]!
                    if(L==0):
                        #str Rx,[Ry],Rz!
                    elif(L==1):
                        #ldr Rx,[Ry],Rz!

Answer 1

The if-elif block are empty. Python expects a sentence after the conditions.

If you want to have an empty block you can use the keyword pass :

if (...):
    pass
elif (...):
    pass

Note: Comments #... are ommited, and not considered as statements.

Answer 2

no wonder, there's nothing between if and elif :

                if(L==0):   
                elif(L==1):

this is a syntax error.

you can put a pass in between, if you don't care about that branch:

                if(L==0):  
                  pass 
                elif(L==1):
                  pass

Answer 3

You don't have any code (just a comment) after the if statement where the error occurs.

If you add pass wherever you don't have code (just a comment), things should start to work.