How to use the icalendar.compat.unicode_type function in icalendar

try:
            recur = cls()
            for pairs in ical.split(';'):
                try:
                    key, vals = pairs.split('=')
                except ValueError:
                    # E.g. incorrect trailing semicolon, like (issue #157):
                    # FREQ=YEARLY;BYMONTH=11;BYDAY=1SU;
                    continue
                recur[key] = cls.parse_type(key, vals)
            return dict(recur)
        except:
            raise ValueError('Error in recurrence rule: %s' % ical)


class vText(compat.unicode_type):
    """Simple text.
    """

    def __new__(cls, value, encoding=DEFAULT_ENCODING):
        value = to_unicode(value, encoding=encoding)
        self = super(vText, cls).__new__(cls, value)
        self.encoding = encoding
        self.params = Parameters()
        return self

    def __repr__(self):
        return "vText('%s')" % self.to_ical()

    def to_ical(self):
        return escape_char(self).encode(self.encoding)

stack = []  # a stack of components
        comps = []
        for line in Contentlines.from_ical(st):  # raw parsing
            if not line:
                continue

            try:
                name, params, vals = line.parts()
            except ValueError as e:
                # if unable to parse a line within a component
                # that ignores exceptions, mark the component
                # as broken and skip the line. otherwise raise.
                component = stack[-1] if stack else None
                if not component or not component.ignore_exceptions:
                    raise
                component.errors.append((None, unicode_type(e)))
                continue

            uname = name.upper()
            # check for start of component
            if uname == 'BEGIN':
                # try and create one of the components defined in the spec,
                # otherwise get a general Components for robustness.
                c_name = vals.upper()
                c_class = component_factory.get(c_name, Component)
                # If component factory cannot resolve ``c_name``, the generic
                # ``Component`` class is used which does not have the name set.
                # That's opposed to the usage of ``cls``, which represents a
                # more concrete subclass with a name set (e.g. VCALENDAR).
                component = c_class()
                if not getattr(component, 'name', ''):  # undefined components
                    component.name = c_name

def unescape_string(val):
    return val.replace('%2C', ',').replace('%3A', ':')\
              .replace('%3B', ';').replace('%5C', '\\')


def unescape_list_or_string(val):
    if isinstance(val, list):
        return [unescape_string(s) for s in val]
    else:
        return unescape_string(val)


#########################################
# parsing and generation of content lines

class Contentline(compat.unicode_type):
    """A content line is basically a string that can be folded and parsed into
    parts.
    """
    def __new__(cls, value, strict=False, encoding=DEFAULT_ENCODING):
        value = to_unicode(value, encoding=encoding)
        assert '\n' not in value, ('Content line can not contain unescaped '
                                    'new line characters.')
        self = super(Contentline, cls).__new__(cls, value)
        self.strict = strict
        return self

    @classmethod
    def from_parts(cls, name, params, values, sorted=True):
        """Turn a parts into a content line.
        """
        assert isinstance(params, Parameters)

def to_ical(self, sorted=True):
        result = []
        items = list(self.items())
        if sorted:
            items.sort()

        for key, value in items:
            value = param_value(value)
            if isinstance(value, compat.unicode_type):
                value = value.encode(DEFAULT_ENCODING)
            # CaselessDict keys are always unicode
            key = key.upper().encode(DEFAULT_ENCODING)
            result.append(key + b'=' + value)
        return b';'.join(result)

return self

    def to_ical(self):
        if self:
            return b'TRUE'
        return b'FALSE'

    @classmethod
    def from_ical(cls, ical):
        try:
            return cls.BOOL_MAP[ical]
        except:
            raise ValueError("Expected 'TRUE' or 'FALSE'. Got %s" % ical)


class vCalAddress(compat.unicode_type):
    """This just returns an unquoted string.
    """
    def __new__(cls, value, encoding=DEFAULT_ENCODING):
        value = to_unicode(value, encoding=encoding)
        self = super(vCalAddress, cls).__new__(cls, value)
        self.params = Parameters()
        return self

    def __repr__(self):
        return "vCalAddress('%s')" % self.to_ical()

    def to_ical(self):
        return self.encode(DEFAULT_ENCODING)

    @classmethod
    def from_ical(cls, ical):

factory = types_factory.for_property(name)
                component = stack[-1] if stack else None
                if not component:
                    raise ValueError('Property "{prop}" does not have '
                                     'a parent component.'.format(prop=name))
                datetime_names = ('DTSTART', 'DTEND', 'RECURRENCE-ID', 'DUE',
                                  'FREEBUSY', 'RDATE', 'EXDATE')
                try:
                    if name in datetime_names and 'TZID' in params:
                        vals = factory(factory.from_ical(vals, params['TZID']))
                    else:
                        vals = factory(factory.from_ical(vals))
                except ValueError as e:
                    if not component.ignore_exceptions:
                        raise
                    component.errors.append((uname, unicode_type(e)))
                    component.add(name, None, encode=0)
                else:
                    vals.params = params
                    component.add(name, vals, encode=0)

        if multiple:
            return comps
        if len(comps) > 1:
            raise ValueError('Found multiple components where '
                             'only one is allowed: {st!r}'.format(**locals()))
        if len(comps) < 1:
            raise ValueError('Found no components where '
                             'exactly one is required: '
                             '{st!r}'.format(**locals()))
        return comps[0]

def foldline(line, limit=75, fold_sep='\r\n '):
    """Make a string folded as defined in RFC5545
    Lines of text SHOULD NOT be longer than 75 octets, excluding the line
    break.  Long content lines SHOULD be split into a multiple line
    representations using a line "folding" technique.  That is, a long
    line can be split between any two characters by inserting a CRLF
    immediately followed by a single linear white-space character (i.e.,
    SPACE or HTAB).
    """
    assert isinstance(line, compat.unicode_type)
    assert '\n' not in line

    # Use a fast and simple variant for the common case that line is all ASCII.
    try:
        line.encode('ascii')
    except (UnicodeEncodeError, UnicodeDecodeError):
        pass
    else:
        return fold_sep.join(
            line[i:i + limit - 1] for i in range(0, len(line), limit - 1)
        )

    ret_chars = []
    byte_count = 0
    for char in line:
        char_byte_len = len(char.encode(DEFAULT_ENCODING))

def to_unicode(value, encoding='utf-8'):
    """Converts a value to unicode, even if it is already a unicode string.
    """
    if isinstance(value, compat.unicode_type):
        return value
    elif isinstance(value, compat.bytes_type):
        try:
            value = value.decode(encoding)
        except UnicodeDecodeError:
            value = value.decode('utf-8', 'replace')
    return value

def to_ical(self):
        return compat.unicode_type(self).encode('utf-8')

def to_ical(self):
        return compat.unicode_type(self).encode('utf-8')