code: public static EdgeRcClientCredentialProvider fromEdgeRc(String filename, String section)
              throws ConfigurationException, IOException {
          if (filename == null || "".equals(filename)) {
              throw new IllegalArgumentException("filename cannot be null");
          }
          filename = filename.replaceFirst("^~", System.getProperty("user.home"));
          File file = new File(filename);
          return fromEdgeRc(new FileReader(file), section);
      }
docs: Loads an EdgeRc configuration file and returns an {@link EdgeRcClientCredentialProvider} to
  read {@link ClientCredential}s from it.
  
  @param filename a filename pointing to an EdgeRc file
  @param section a config section ({@code null} for the default section)
  @return a {@link EdgeRcClientCredentialProvider}
  @throws ConfigurationException If an error occurs while reading the configuration
  @throws IOException if an I/O error occurs