[Python] What is the length of a python bytecode instruction in CPython?

Python docs on the dis module state that the length of a python bytecode instruction in CPython is 2 bytes (https://docs.python.org/3/library/dis.html)

However, when I disassemble a function and look at the actual bytecode, I see that the instructions only take up 1 byte:

def example_function(x):
if x > 0:
return x + 1
return 0


print(example_function.__code__.co_code.hex())

97007c0064016b44000072057c0064027a00000053007901


dis.dis(example_function)

10 0 RESUME 0

11 2 LOAD_FAST 0 (x)
4 LOAD_CONST 1 (0)
6 COMPARE_OP 68 (>)
10 POP_JUMP_IF_FALSE 5 (to 22)

12 12 LOAD_FAST 0 (x)
14 LOAD_CONST 2 (1)
16 BINARY_OP 0 (+)
20 RETURN_VALUE

13 >> 22 RETURN_CONST 1 (0)



Are they variable in length?

The instruction list defined in dis.opname does have a few instructions longer than 1 byte, but how does then the interpreter know when it's 1 byte and when it's 2 bytes?

As you can see above, I've tried disassembling the code to see for myself and inspected the docs.

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