How to use the pycodestyle.readlines function in pycodestyle

def run_tests(filename):
        """Run all the tests from a file."""
        # Skip tests meant for higher versions of python
        ver_match = re.search(r'python(\d)(\d)?\.py$', filename)
        if ver_match:
            test_against_version = tuple(int(val or 0)
                                         for val in ver_match.groups())
            if sys.version_info < test_against_version:
                return
        lines = readlines(filename) + ['#:\n']
        line_offset = 0
        codes = ['Okay']
        testcase = []
        count_files = report.counters['files']
        for index, line in enumerate(lines):
            if not line.startswith('#:'):
                if codes:
                    # Collect the lines of the test case
                    testcase.append(line)
                continue
            if codes and index:
                if 'noeol' in codes:
                    testcase[-1] = testcase[-1].rstrip('\n')
                codes = [c for c in codes
                         if c not in ('Okay', 'noeol')]
                # Run the checker

def get_lines(filename):
    if filename in ('stdin', '-', None):
        return stdin_utils.stdin_get_value().splitlines(True)
    else:
        return pep8.readlines(filename)

def load_file(self):
        """Loads the file in a way that auto-detects source encoding and deals
        with broken terminal encodings for stdin.

        Stolen from flake8_import_order because it's good.
        """

        if self.filename in ("stdin", "-", None):
            self.filename = "stdin"
            self.lines = pycodestyle.stdin_get_value().splitlines(True)
        else:
            self.lines = pycodestyle.readlines(self.filename)

        if not self.tree:
            self.tree = ast.parse("".join(self.lines))

def _load_source(self):
        """Loads the file in a way that auto-detects source encoding and deals
        with broken terminal encodings for stdin.

        Stolen from flake8_import_order because it's good.
        """

        if self.filename in ("stdin", "-", None):
            self.filename = "stdin"
            self.lines = stdin_utils.stdin_get_value().splitlines(True)
        else:
            self.lines = pycodestyle.readlines(self.filename)
        if not self.tree:
            self.tree = ast.parse("".join(self.lines))

def get_tokens(filename):
    if filename == 'stdin':
        file_contents = stdin_utils.stdin_get_value().splitlines(True)
    else:
        file_contents = pycodestyle.readlines(filename)
    file_contents_iter = iter(file_contents)

    def file_contents_next():
        return next(file_contents_iter)

    for t in tokenize.generate_tokens(file_contents_next):
        yield Token(t)

def load_file(self):
        """
        Loads the file in a way that auto-detects source encoding and deals
        with broken terminal encodings for stdin.
        Stolen from flake8_import_order because it's good.
        """

        if self.filename in ("stdin", "-", None):
            self.filename = "stdin"
            self.lines = pycodestyle.stdin_get_value().splitlines(True)
        else:
            self.lines = pycodestyle.readlines(self.filename)

        if not self.tree:
            self.tree = ast.parse("".join(self.lines))

def load_file(self):
        if self.filename in ("stdin", "-", None):
            self.filename = "stdin"
            self.lines = pycodestyle.stdin_get_value().splitlines(True)
        else:
            self.lines = pycodestyle.readlines(self.filename)

        if not self.tree:
            self.tree = ast.parse("".join(self.lines))