How to use the macholib.util.fileview function in macholib

def load(self, fh):
        fh = fileview(fh, self.offset, self.size)
        fh.seek(0)

        self.sizediff = 0
        kw = {'_endian_': self.endian}
        header = self.mach_header.from_fileobj(fh, **kw)
        self.header = header
        if header.magic != self.MH_MAGIC:
            raise ValueError("header has magic %08x, expecting %08x" % (
                header.magic, self.MH_MAGIC))

        cmd = self.commands = []

        self.filetype = MH_FILETYPE_SHORTNAMES[header.filetype]

        read_bytes = 0
        low_offset = sys.maxint

def write(self, fileobj):
        fileobj = fileview(fileobj, self.offset, self.size)
        fileobj.seek(0)

        # serialize all the mach-o commands
        self.synchronize_size()

        self.header.to_fileobj(fileobj)
        for lc, cmd, data in self.commands:
            lc.to_fileobj(fileobj)
            cmd.to_fileobj(fileobj)

            if isinstance(data, unicode):
                fileobj.write(data.encode(sys.getfilesystemencoding()))
            
            elif isinstance(data, (bytes, str)):
                fileobj.write(data)
            else:

def write(self, fileobj):
        fileobj = fileview(fileobj, self.offset, self.size)
        fileobj.seek(0)

        # serialize all the mach-o commands
        self.synchronize_size()

        self.header.to_fileobj(fileobj)
        for lc, cmd, data in self.commands:
            lc.to_fileobj(fileobj)
            cmd.to_fileobj(fileobj)

            if isinstance(data, unicode):
                fileobj.write(data.encode(sys.getfilesystemencoding()))
            
            elif isinstance(data, (bytes, str)):
                fileobj.write(data)
            else:

def load(self, fh):
        fh = fileview(fh, self.offset, self.size)
        fh.seek(0)

        self.sizediff = 0
        kw = {'_endian_': self.endian}
        header = self.mach_header.from_fileobj(fh, **kw)
        self.header = header
        #if header.magic != self.MH_MAGIC:
        #    raise ValueError("header has magic %08x, expecting %08x" % (
        #        header.magic, self.MH_MAGIC))

        cmd = self.commands = []

        self.filetype = self.get_filetype_shortname(header.filetype)

        read_bytes = 0
        low_offset = sys.maxsize

def load(self, fh):
        fh = fileview(fh, self.offset, self.size)
        fh.seek(0)

        self.sizediff = 0
        kw = {'_endian_': self.endian}
        header = self.mach_header.from_fileobj(fh, **kw)
        self.header = header
        if header.magic != self.MH_MAGIC:
            raise ValueError("header has magic %08x, expecting %08x" % (
                header.magic, self.MH_MAGIC))

        cmd = self.commands = []

        self.filetype = MH_FILETYPE_SHORTNAMES[header.filetype]

        read_bytes = 0
        low_offset = sys.maxsize

def write(self, fileobj):
        fileobj = fileview(fileobj, self.offset, self.size)
        fileobj.seek(0)

        # serialize all the mach-o commands
        self.synchronize_size()

        self.header.to_fileobj(fileobj)
        for lc, cmd, data in self.commands:
            lc.to_fileobj(fileobj)
            cmd.to_fileobj(fileobj)

            if sys.version_info[0] == 2:
                if isinstance(data, unicode):
                    fileobj.write(data.encode(sys.getfilesystemencoding()))

                elif isinstance(data, (bytes, str)):
                    fileobj.write(data)