Add document for extended PySpark specific logging functions

sql/core/src/main/scala/org/apache/spark/sql/Column.scala

@@ -171,19 +171,37 @@ class Column(val expr: Expression) extends Logging {
     Column.fn(name, this, lit(other))
   }
 
-  // For PySpark logging
-  private def fn(
-      name: String, pysparkLoggingInfo: java.util.Map[String, String]): Column = {
-    withOrigin(Some(pysparkLoggingInfo)) {
-      Column.fn(name, this)
-    }
-  }
+  /**
+   * A version of the `fn` method specifically designed for binary operations in PySpark
+   * that require logging information.
+   * This method is used when the operation involves another Column.
+   *
+   * @param name               The name of the operation to be performed.
+   * @param other              The other Column involved in the operation.
+   * @param pysparkLoggingInfo A map containing logging information such as the fragment and
+   *                           call site from PySpark.
+   * @return A Column resulting from the operation.
+   */
   private def fn(
       name: String, other: Column, pysparkLoggingInfo: java.util.Map[String, String]): Column = {
     withOrigin(Some(pysparkLoggingInfo)) {
       Column.fn(name, this, other)
     }
   }
+
+  /**
+   * A version of the `fn` method for binary operations that involve a value other than a Column
+   * and require PySpark logging information.
+   * This method is used to apply an operation with any value, converting it to a Column
+   * if necessary.
+   *
+   * @param name               The name of the operation to be performed.
+   * @param other              The value to be used in the operation, which will be converted to a
+   *                           Column if not already one.
+   * @param pysparkLoggingInfo A map containing logging information such as the fragment and
+   *                           call site from PySpark.
+   * @return A Column resulting from the operation.
+   */
   private def fn(
       name: String, other: Any, pysparkLoggingInfo: java.util.Map[String, String]): Column = {
     withOrigin(Some(pysparkLoggingInfo)) {