If Statements and Comparisons returns a syntax error

[DarkAlchemyXEX]

I'm self teaching python and need a bit of help . I'm trying to figure out why my code gives me a syntax error.

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def max_num(num1, num2, num3):     if num1 >= num2 and num1 >= num3:         return num1     elif num_2 >= num1 >= num3:         return num2     else:         return num3                               print(max_num(3, 4, 5))

I know the answer is 5 but when I try to run the code I get

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Traceback (most recent call last):   File "/data/user/0/ru.iiec.pydroid3/files/accomp_files/iiec_run/iiec_run.py", line 31, in <module>     start(fakepyfile,mainpyfile)   File "/data/user/0/ru.iiec.pydroid3/files/accomp_files/iiec_run/iiec_run.py", line 30, in start     exec(open(mainpyfile).read(),  __main__.__dict__)   File "<string>", line 11, in <module>   File "<string>", line 4, in max_num NameError: name 'num_2' is not defined   [Program finished]

[ibreeden]

NameError: name 'num_2' is not defined

That is the message and it means you use the variable "num_2", but you should use "num2".

[DarkAlchemyXEX]

Thank you