<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_installed_version(dist_name, working_set=None):
 """Get the installed version of dist_name avoiding pkg_resources cache"""

    # Create a requirement that we'll look for inside of setuptools.
    req = pkg_resources.Requirement.parse(dist_name)

    if working_set is None:
        # We want to avoid having this cached, so we need to construct a new
        # working set each time.
        working_set = pkg_resources.WorkingSet()

    # Get the installed distribution from our working set
    dist = working_set.find(req)

    # Check to see if we got an installed distribution or not, if we did
    # we want to return it's version.
    return dist.version if dist else None