File configure.ac of Package failed_libfwnt

```m4
# Corrected configure.ac to ensure proper Python installation paths

# Check for Python version and set installation directories
AC_ARG_WITH([python-prefix],
    [AS_HELP_STRING([--with-python-prefix=PREFIX],
        [Specify the prefix for Python installation @<:@default=/usr@:>@])],
    [python_prefix="$withval"],
    [python_prefix="/usr"])

# Set Python library directory
if test "x$python_prefix" != "xno"; then
    pythondir="${python_prefix}/lib64/python${PYTHON_VERSION}/site-packages"
    AC_SUBST(pythondir)
fi

# Rest of the configure.ac remains unchanged
```

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