Filter the last week of user actions.

def GetReportData(self, get_report_args, token):
    """Filter the last week of user actions."""
    ret = rdf_report_plugins.ApiReportData(
        representation_type=RepresentationType.PIE_CHART)

    counts = self._GetUserCounts(get_report_args, token)
    for username in aff4_users.GRRUser.SYSTEM_USERS:
      del counts[username]

    ret.pie_chart.data = [
        rdf_report_plugins.ApiReportDataPoint1D(x=count, label=user)
        for user, count in sorted(iteritems(counts))
    ]

    return ret