Programs that can run with any version of Python must begin with
#!/usr/bin/python or #!/usr/bin/env python (the
former is preferred). They must also specify a dependency on
python, with a versioned dependency if necessary.
If the program needs the python module foo, it must depend on the
real package providing this module, usually python-foo but this
name might vary when the package ships multiple modules.
3.1.1 Programs Shipping Private Modules
A program using /usr/bin/python as interpreter can come up with
private Python modules. These modules should be installed in
/usr/share/module, or
/usr/lib/module if the modules are
architecture-dependent (e.g. extensions).
The rules explained in Modules Byte-Compilation,
Section 2.6 apply to those private modules: the byte-compiled modules must
not be shipped with the binary package, they should be generated in the
package's postinst, using the current default Python version, and removed in
the prerm. Modules should be byte-compiled using the current default Python
version.
Programs that have private compiled extensions must either handle multiple
version support themselves, or declare a tight dependency on the current Python
version (e.g. Depends: python (>= 2.4), python (<= 2.5).
No tools currently exist to alleviate this situation.
3.2 Programs Using a Particular Python Version
A program which requires a specific version of Python must begin with
#!/usr/bin/pythonX.Y (or
#!/usr/bin/env pythonX.Y). It must also
specify a dependency on pythonX.Y and on any
pythonX.Y-foo package providing necessary
modules. It should not depend on any python-foo package, unless
it requires a specific version of the package (since virtual packages cannot be
versioned). If this is the case, it should depend on both the virtual package
and the main package (e.g. Depends: python2.4-foo, python-foo (>=
1.0)).
The notes on installation directories and byte-compilation for programs that
support any version of Python also apply to programs supporting only a single
Python version. Modules to be byte-compiled should use the same Python version
as the package itself.