How to use the doc8.checks.LineCheck function in doc8

if cfg.get("verbose"):
                print("  Running check '%s'" % check_name)
            if isinstance(c, checks.ContentCheck):
                for line_num, code, message in c.report_iter(f):
                    if code in targeted_ignoreables:
                        continue
                    if not isinstance(line_num, (float, int)):
                        line_num = "?"
                    if cfg.get("verbose"):
                        print(
                            "    - %s:%s: %s %s" % (f.filename, line_num, code, message)
                        )
                    else:
                        print("%s:%s: %s %s" % (f.filename, line_num, code, message))
                    error_counts[check_name] += 1
            elif isinstance(c, checks.LineCheck):
                for line_num, line in enumerate(f.lines_iter(), 1):
                    for code, message in c.report_iter(line):
                        if code in targeted_ignoreables:
                            continue
                        if cfg.get("verbose"):
                            print(
                                "    - %s:%s: %s %s"
                                % (f.filename, line_num, code, message)
                            )
                        else:
                            print(
                                "%s:%s: %s %s" % (f.filename, line_num, code, message)
                            )
                        error_counts[check_name] += 1
            else:
                raise TypeError("Unknown check type: %s, %s" % (type(c), c))

    @abc.abstractmethod
    def report_iter(self, line):
        pass


class CheckTrailingWhitespace(LineCheck):
    _TRAILING_WHITESPACE_REGEX = re.compile(r"\s$")
    REPORTS = frozenset(["D002"])

    def report_iter(self, line):
        if self._TRAILING_WHITESPACE_REGEX.search(line):
            yield ("D002", "Trailing whitespace")


class CheckIndentationNoTab(LineCheck):
    _STARTING_WHITESPACE_REGEX = re.compile(r"^(\s+)")
    REPORTS = frozenset(["D003"])

    def report_iter(self, line):
        match = self._STARTING_WHITESPACE_REGEX.search(line)
        if match:
            spaces = match.group(1)
            if "\t" in spaces:
                yield ("D003", "Tabulation used for indentation")


class CheckCarriageReturn(LineCheck):
    REPORTS = frozenset(["D004"])

    def report_iter(self, line):
        if "\r" in line:

yield ("D002", "Trailing whitespace")


class CheckIndentationNoTab(LineCheck):
    _STARTING_WHITESPACE_REGEX = re.compile(r"^(\s+)")
    REPORTS = frozenset(["D003"])

    def report_iter(self, line):
        match = self._STARTING_WHITESPACE_REGEX.search(line)
        if match:
            spaces = match.group(1)
            if "\t" in spaces:
                yield ("D003", "Tabulation used for indentation")


class CheckCarriageReturn(LineCheck):
    REPORTS = frozenset(["D004"])

    def report_iter(self, line):
        if "\r" in line:
            yield ("D004", "Found literal carriage return")


class CheckNewlineEndOfFile(ContentCheck):
    REPORTS = frozenset(["D005"])

    def __init__(self, cfg):
        super(CheckNewlineEndOfFile, self).__init__(cfg)

    def report_iter(self, parsed_file):
        if parsed_file.lines and not parsed_file.lines[-1].endswith(b"\n"):
            yield (len(parsed_file.lines), "D005", "No newline at end of file")

    @abc.abstractmethod
    def report_iter(self, parsed_file):
        pass


@six.add_metaclass(abc.ABCMeta)
class LineCheck(object):
    def __init__(self, cfg):
        self._cfg = cfg

    @abc.abstractmethod
    def report_iter(self, line):
        pass


class CheckTrailingWhitespace(LineCheck):
    _TRAILING_WHITESPACE_REGEX = re.compile(r"\s$")
    REPORTS = frozenset(["D002"])

    def report_iter(self, line):
        if self._TRAILING_WHITESPACE_REGEX.search(line):
            yield ("D002", "Trailing whitespace")


class CheckIndentationNoTab(LineCheck):
    _STARTING_WHITESPACE_REGEX = re.compile(r"^(\s+)")
    REPORTS = frozenset(["D003"])

    def report_iter(self, line):
        match = self._STARTING_WHITESPACE_REGEX.search(line)
        if match:
            spaces = match.group(1)