cdm/src/main/java/ucar/nc2/iosp/noaa/Ghcnm.java
static private NetcdfFile open(String filename) throws IOException {
    Ghcnm iosp = new Ghcnm();
    RandomAccessFile raf = new RandomAccessFile(filename, "r");
    NetcdfFile ncfile = new NetcdfFileSubclass(iosp, filename);
    iosp.open(raf, ncfile, null);
    return ncfile;
  }
static private NetcdfFile open(String filename) throws IOException {
    Ghcnm iosp = new Ghcnm();
    RandomAccessFile raf = new RandomAccessFile(filename, "r");
    NetcdfFile ncfile = new NetcdfFileSubclass(iosp, filename);
    iosp.open(raf, ncfile, null);
    return ncfile;
  }
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