bpo-44426: Use of 'complex' as a C variable name confuses Sphinx; change it to 'num'. (GH-26744) (GH-26760)

(cherry picked from commit 7247f6f)

Author: miss-islington

Doc/c-api/complex.rst

@@ -46,9 +46,9 @@ pointers.  This is consistent throughout the API.
    :c:type:`Py_complex` representation.
 
 
-.. c:function:: Py_complex _Py_c_neg(Py_complex complex)
+.. c:function:: Py_complex _Py_c_neg(Py_complex num)
 
-   Return the negation of the complex number *complex*, using the C
+   Return the negation of the complex number *num*, using the C
    :c:type:`Py_complex` representation.