How to use the rospkg.get_test_results_dir function in rospkg

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# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
# Revision $Id$

"""
test_results_dir.py simply prints the directory that rosunit/rostest
results are stored in.
"""

from __future__ import print_function

import rospkg

print(rospkg.get_test_results_dir())

def read_all(filter_=[]):
    """
    Read in the test_results and aggregate into a single Result object
    @param filter_: list of packages that should be processed
    @type filter_: [str]
    @return: aggregated result
    @rtype: L{Result}
    """
    dir_ = rospkg.get_test_results_dir()
    root_result = Result('ros', 0, 0, 0)
    if not os.path.exists(dir_):
        return root_result
    for d in os.listdir(dir_):
        if filter_ and d not in filter_:
            continue
        subdir = os.path.join(dir_, d)
        if os.path.isdir(subdir):
            for filename in os.listdir(subdir):
                if filename.endswith('.xml'):
                    filename = os.path.join(subdir, filename)
                    result = read(filename, os.path.basename(subdir))
                    root_result.accumulate(result)
    return root_result

def prepare_dirs(output_dir_name):
    test_results_dir = rospkg.get_test_results_dir()
    print('will read test results from', test_results_dir)
    output_dir = os.path.join(test_results_dir, output_dir_name)
    if not os.path.exists(output_dir):
        print('creating directory', output_dir)
        os.makedirs(output_dir)
    return test_results_dir, output_dir

def xml_results_file(test_pkg, test_name, is_rostest=False, env=None):
    """
    @param test_pkg: name of test's package
    @type  test_pkg: str
    @param test_name str: name of test
    @type  test_name: str
    @param is_rostest: True if the results file is for a rostest-generated unit instance
    @type  is_rostest: bool
    @return: name of xml results file for specified test
    @rtype:  str
    """
    test_dir = os.path.join(rospkg.get_test_results_dir(env=env), test_pkg)
    if not os.path.exists(test_dir):
        try:
            makedirs_with_parent_perms(test_dir)
        except OSError as error:
            raise IOError('cannot create test results directory [%s]: %s' % (test_dir, str(error)))

    # #576: strip out chars that would bork the filename
    # this is fairly primitive, but for now just trying to catch some common cases
    for c in ' "\'&$!`/\\':
        if c in test_name:
            test_name = test_name.replace(c, '_')
    if is_rostest:
        return os.path.join(test_dir, 'rostest-%s.xml' % test_name)
    else:
        return os.path.join(test_dir, 'rosunit-%s.xml' % test_name)