code: public static <K, VV> GraphCsvReader fromCsvReader(String edgesPath,
  			final MapFunction<K, VV> vertexValueInitializer, ExecutionEnvironment context) {
  		return new GraphCsvReader(edgesPath, vertexValueInitializer, context);
  	}
docs: Creates a graph from a CSV file of edges. Vertices will be created automatically and
  Vertex values can be initialized using a user-defined mapper.
  
  @param edgesPath a path to a CSV file with the Edge data
  @param vertexValueInitializer the mapper function that initializes the vertex values.
  It allows to apply a map transformation on the vertex ID to produce an initial vertex value.
  @param context the execution environment.
  @return An instance of {@link org.apache.flink.graph.GraphCsvReader},
  on which calling methods to specify types of the Vertex ID, Vertex Value and Edge value returns a Graph.
  
  @see org.apache.flink.graph.GraphCsvReader#types(Class, Class, Class)
  @see org.apache.flink.graph.GraphCsvReader#vertexTypes(Class, Class)
  @see org.apache.flink.graph.GraphCsvReader#edgeTypes(Class, Class)
  @see org.apache.flink.graph.GraphCsvReader#keyType(Class)