def _read_single(parser, filepath):
from os import path<EOL>global packages<EOL>if path.isfile(filepath):<EOL><INDENT>parser.readfp(open(filepath))<EOL><DEDENT>
Reads a single config file into the parser, silently failing if the file
    does not exist.

    Args:
    parser (ConfigParser): parser to read the file into.
    filepath (str): full path to the config file.