foo.c:1:1: error: unknown type name 'def'
    1 | def fb(n):
      | ^~~
foo.c: In function 'fb':
foo.c:1:10: error: expected declaration specifiers before ':' token
    1 | def fb(n):
      |          ^
foo.c:1:5: warning: type of 'n' defaults to 'int' [-Wimplicit-int]
    1 | def fb(n):
      |     ^~
foo.c:8: warning: control reaches end of non-void function [-Wreturn-type]
    8 | print(fb(n))
      | 

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