Further to that if you tried to create a new project on a directory that contains either of these two files you would get an error similar to the one shown below on the Pydev Project creation dialog:
In this situation you need to either delete the .project and .pydevproject files, or import the project. Import is a better way to go as that way you will not have to reconfigure any settings that are already set up and stored in the .project or .pydevproject files..
To import an existing project you need to bring up the import dialog. As with almost all things in eclipse there is more than one way to bring up this dialog:
Both of the actions described above will create the following import dialog:
As shown above select Existing Projects into Workspace and then click Next. After you hit next the following dialog box gets created. The numbers on the dialog correspond to the steps that are described below:
Now press finish and eclipse will import the project into your eclipse session.