code: @GET
      @Path("/guid/{guid}/classification/{classificationName}")
      @Produces(Servlets.JSON_MEDIA_TYPE)
      public AtlasClassification getClassification(@PathParam("guid") String guid, @PathParam("classificationName") final String classificationName) throws AtlasBaseException {
          AtlasPerfTracer perf = null;
  
          try {
              if (AtlasPerfTracer.isPerfTraceEnabled(PERF_LOG)) {
                  perf = AtlasPerfTracer.getPerfTracer(PERF_LOG, "EntityREST.getClassification(" + guid + "," + classificationName + ")");
              }
  
              if (StringUtils.isEmpty(guid)) {
                  throw new AtlasBaseException(AtlasErrorCode.INSTANCE_GUID_NOT_FOUND, guid);
              }
  
              ensureClassificationType(classificationName);
              return entitiesStore.getClassification(guid, classificationName);
          } finally {
              AtlasPerfTracer.log(perf);
          }
      }
docs: Gets the list of classifications for a given entity represented by a guid.
  @param guid globally unique identifier for the entity
  @return classification for the given entity guid