Having dist packages before users packages actually makes sense IMHO.
But anyway, you have two options here, the bad one and the right one.
The bad one is to redefine your PYTHONPATH environment variable to put
your local package's dir before site-wide packages. It's as simple as this,
but don't complain when your system breaks because you shadowed a critical
package with some incompatible version.
The right way to try out specific versions of a package without breaking
anything is of course to use virtualenv.