def CheckBegin(self, filename, clean_lines, linenum, error):
pass<EOL>
Run checks that applies to text up to the opening brace.

        This is mostly for checking the text after the class identifier
        and the "{", usually where the base class is specified.  For other
        blocks, there isn't much to check, so we always pass.

        Args:
          filename: The name of the current file.
          clean_lines: A CleansedLines instance containing the file.
          linenum: The number of the line to check.
          error: The function to call with any errors found.