There are some minimum modifications that should be made in configure.ac. The file contains a significant amount of information in the form of comments, so it is possible to discern your needs while editing. For more advanced usage, it is recommended to refer to the see Autoconf manual.
In this file you will see a macro called AC_INIT. This is a
standard Autoconf macro. The arguments to this are automatically
generated from the PKG-INFO file that you used. These three
values are used extensively in the files modified by the configure
script, so it is important that they be correct.
Further down, you will also find a macro called PC_INIT. This
is the core macro of pyconfigure. This will build the code necessary
to find a suitable Python interpreter on the user's computer. To that
end, you can pass arguments to this macro which specify the minimum
and/or maximum supported Python versions.
While the default configure.ac script will likely be sufficient for a basic Python-based project, it may be made to be much more powerful for packages with more complex needs. To that end, several Autoconf macros are provided in the file m4/python.m4 to allow the developer to write robust tests See Autoconf macros. Note that when you distribute your software, you must include this directory and file with your distribution if you also distribute your configure.ac file.
Once you modify your configure.ac to your liking, you must regenerate your configure script with the bootstrap.sh script that is generated by pyconfigure.
$ ./bootstrap.sh
A full explanation of the general use of Autoconf macros is beyond the scope of this document, however it is worth presenting some examples.