<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_pkglist():
 """ Return list of all installed packages Note: It returns one project name per pkg no matter how many versions of a particular package is installed @returns: list of project name strings for every installed pkg """


    dists = Distributions()
    projects = []
    for (dist, _active) in dists.get_distributions("all"):
        if dist.project_name not in projects:
            projects.append(dist.project_name)
    return projects