How to use the reprozip.utils.PY3 function in reprozip

INSERT INTO "opened_files" VALUES(1,0,'/usr',12345678902001,4,1,1);
INSERT INTO "opened_files" VALUES(2,0,'/lib/ld.so',12345678902003,1,0,2);
INSERT INTO "opened_files" VALUES(3,1,'/usr/bin',12345678902004,4,1,3);
INSERT INTO "executed_files" VALUES(1,'/usr/bin/id',1,12345678902006,4,'id',
    'RUN=third','/home/vagrant');
            ''',
            schema + '''
INSERT INTO "processes" VALUES(0,0,NULL,12345678903001,0,1);
INSERT INTO "opened_files" VALUES(0,0,'/home',12345678903001,4,1,0);
INSERT INTO "executed_files" VALUES(1,'/bin/false',0,12345678903002,0,'false',
    'RUN=fourth','/home');
            ''']

        for i, dat in enumerate(sql_data):
            trace = self.tmpdir / ('trace%d.sqlite3' % i)
            if PY3:
                conn = sqlite3.connect(str(trace))
            else:
                conn = sqlite3.connect(trace.path)
            conn.row_factory = sqlite3.Row
            conn.executescript(dat + 'COMMIT;')
            conn.commit()
            conn.close()

            traces.append(trace)

        target = self.tmpdir / 'target'
        traceutils.combine_traces(traces, target)
        target = target / 'trace.sqlite3'

        if PY3:
            conn = sqlite3.connect(str(target))

def print_db(database):
    """Prints out database content.
    """
    assert database.is_file()
    if PY3:
        # On PY3, connect() only accepts unicode
        conn = sqlite3.connect(str(database))
    else:
        conn = sqlite3.connect(database.path)
    conn.row_factory = sqlite3.Row
    conn.text_factory = lambda x: unicode_(x, 'utf-8', 'replace')

    cur = conn.cursor()
    rows = cur.execute(
        '''
        SELECT id, parent, timestamp, exitcode
        FROM processes;
        ''')
    print("\nProcesses:")
    header = "+------+--------+-------+------------------+"
    print(header)

def combine_traces(traces, target):
    """Combines multiple trace databases into one.

    The runs from the original traces are appended ('run_id' field gets
    translated to avoid conflicts).

    :param traces: List of trace database filenames.
    :type traces: [Path]
    :param target: Directory where to write the new database and associated
        configuration file.
    :type target: Path
    """
    # We are probably overwriting one of the traces we're reading, so write to
    # a temporary file first then move it
    fd, output = Path.tempfile('.sqlite3', 'reprozip_combined_')
    if PY3:
        # On PY3, connect() only accepts unicode
        conn = sqlite3.connect(str(output))
    else:
        conn = sqlite3.connect(output.path)
    os.close(fd)
    conn.row_factory = sqlite3.Row

    # Create the schema
    create_schema(conn)

    # Temporary database with lookup tables
    conn.execute(
        '''
        ATTACH DATABASE '' AS maps;
        ''')
    conn.execute(

def write_configuration(directory, sort_packages, find_inputs_outputs,
                        overwrite=False):
    """Writes the canonical YAML configuration file.
    """
    database = directory / 'trace.sqlite3'

    if PY3:
        # On PY3, connect() only accepts unicode
        conn = sqlite3.connect(str(database))
    else:
        conn = sqlite3.connect(database.path)
    conn.row_factory = sqlite3.Row

    # Reads info from database
    files, inputs, outputs = get_files(conn)

    # Identifies which file comes from which package
    if sort_packages:
        files, packages = identify_packages(files)
    else:
        packages = []

    # Writes configuration file

def write_configuration(directory, sort_packages, find_inputs_outputs,
                        overwrite=False):
    """Writes the canonical YAML configuration file.
    """
    database = directory / 'trace.sqlite3'

    assert database.is_file()
    if PY3:
        # On PY3, connect() only accepts unicode
        conn = sqlite3.connect(str(database))
    else:
        conn = sqlite3.connect(database.path)
    conn.row_factory = sqlite3.Row

    # Reads info from database
    files, inputs, outputs = get_files(conn)

    # Identifies which file comes from which package
    if sort_packages:
        files, packages = identify_packages(files)
    else:
        packages = []

    # Writes configuration file