private void checkBuiltInScalarFunctionInput(FunctionExpression functionExpression) {
    BuiltInScalarFunctionHelperFactory.createHelper(functionExpression.getFunctionName())
        .checkBuiltInScalarFunctionInputSize(functionExpression);
  }
function for parsing file path used by LOAD statement.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/parser/ASTVisitor.java