code: def lit(v, data_type: DataType = None) -> Expression:
      """
      Creates a SQL literal.
  
      The data type is derived from the object's class and its value. For example, `lit(12)` leads
      to `INT`, `lit("abc")` leads to `CHAR(3)`.
  
      Example:
      ::
  
          >>> tab.select(col("key"), lit("abc"))
      """
      if data_type is None:
          return _unary_op("lit", v)
      else:
          return _binary_op("lit", v, _to_java_data_type(data_type))
  
imports: from typing import Union
  from pyflink import add_version_doc
  from pyflink.java_gateway import get_gateway
  from pyflink.table.expression import Expression, _get_java_expression, TimePointUnit, JsonOnNull
  from pyflink.table.types import _to_java_data_type, DataType
  from pyflink.table.udf import UserDefinedFunctionWrapper
  from pyflink.util.java_utils import to_jarray, load_java_class
label_desc: Use image node_id 9 for calling a global function with example usage: lit(v, data_type) and returns: _unary_op, _binary_op