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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def Open(self, file_object, wal_file_object=None):
 """Opens a SQLite database file. Since pysqlite cannot read directly from a file-like object a temporary copy of the file is made. After creating a copy the database file this function sets up a connection with the database and determines the names of the tables. Args: file_object (dfvfs.FileIO):
 file-like object. wal_file_object (Optional[dfvfs.FileIO]):
 file-like object for the Write-Ahead Log (WAL) file. Raises: IOError: if the file-like object cannot be read. OSError: if the file-like object cannot be read. sqlite3.DatabaseError: if the database cannot be parsed. ValueError: if the file-like object is missing. """

    if not file_object:
      raise ValueError('Missing file object.')

    # TODO: Current design copies the entire file into a buffer
    # that is parsed by each SQLite parser. This is not very efficient,
    # especially when many SQLite parsers are ran against a relatively
    # large SQLite database. This temporary file that is created should
    # be usable by all SQLite parsers so the file should only be read
    # once in memory and then deleted when all SQLite parsers have completed.

    # TODO: Change this into a proper implementation using APSW
    # and virtual filesystems when that will be available.
    # Info: http://apidoc.apsw.googlecode.com/hg/vfs.html#vfs and
    # http://apidoc.apsw.googlecode.com/hg/example.html#example-vfs
    # Until then, just copy the file into a tempfile and parse it.

    temporary_file = tempfile.NamedTemporaryFile(
        delete=False, dir=self._temporary_directory)

    try:
      self._CopyFileObjectToTemporaryFile(file_object, temporary_file)
      self._temp_db_file_path = temporary_file.name

    except IOError:
      os.remove(temporary_file.name)
      raise

    finally:
      temporary_file.close()

    if wal_file_object:
      # Create WAL file using same filename so it is available for
      # sqlite3.connect()
      temporary_filename = '{0:s}-wal'.format(self._temp_db_file_path)
      temporary_file = open(temporary_filename, 'wb')
      try:
        self._CopyFileObjectToTemporaryFile(wal_file_object, temporary_file)
        self._temp_wal_file_path = temporary_filename

      except IOError:
        os.remove(temporary_filename)
        raise

      finally:
        temporary_file.close()

    self._database = sqlite3.connect(self._temp_db_file_path)
    try:
      self._database.row_factory = sqlite3.Row
      cursor = self._database.cursor()

      sql_results = cursor.execute(self.SCHEMA_QUERY)

      self.schema = {
          table_name: ' '.join(query.split())
          for table_name, query in sql_results}

    except sqlite3.DatabaseError as exception:
      self._database.close()
      self._database = None

      os.remove(self._temp_db_file_path)
      self._temp_db_file_path = ''
      if self._temp_wal_file_path:
        os.remove(self._temp_wal_file_path)
        self._temp_wal_file_path = ''

      logger.debug(
          'Unable to parse SQLite database: {0:s} with error: {1!s}'.format(
              self._filename, exception))
      raise

    self._is_open = True