(CNN) At a Saturday night rally in Harrisburg, Pennsylvania, designed to celebrate his first 100 days in office, Donald Trump read the lyrics from a song called "The Snake."

Here are the lyrics of the song -- by Al Wilson -- that Trump read (full song is here ):

On her way to work one morning

Down the path alongside the lake

A tender-hearted woman saw a poor half-frozen snake

His pretty colored skin had been all frosted with the dew

"Oh well," she cried, "I'll take you in and I'll take care of you"

Now she clutched him to her bosom, "You're so beautiful," she cried

"But if I hadn't brought you in by now you might have died"

Now she stroked his pretty skin and then she kissed and held him tight

But instead of saying thanks, that snake gave her a vicious bite

This isn't the first time Trump has read the lyrics to "The Snake." He repeatedly did so during the 2016 campaign -- using it as an not-subtle allegory for the situation on the border with Mexico and in reference to the Syrian refugee crisis, warning against allowing potential terrorists into the country.

JUST WATCHED President Trump reads 'The Snake' Replay More Videos ... MUST WATCH President Trump reads 'The Snake' 01:48

As you can see, Trump makes explicit the fact that the snake represents the undocumented workers coming into the country, and the woman is our current U.S. border policy. It's a striking image: Undocumented workers might look weak and pitiable but, in the end, they will bite you for trying to help.

And, it worked for Trump during the 2016 campaign. For many of his voters, "The Snake" perfectly encapsulated their views of undocumented workers: Sneaking into the US under false pretenses and then immediately turning on the same people whose country they had entered. Trump stoked this idea by regularly citing heinous crimes committed by people who had come to the country illegally.

(It's worth noting here that Trump is wrong in his assertions that immigrants generally -- and illegal immigrants specifically -- are more likely to commit crimes than the average American-born citizen. Read this on that.)

But, Trump is President now. And, up until Saturday night in Harrisburg, he hadn't done a dramatic reading of "The Snake." You might have been led to conclude that he understood that casting people trying to come to the US -- legally or illegally -- as a snake who will eventually bite the hand that feeds it is not exactly the stuff of presidents.

He had, in fact, not drawn that conclusion. And, I think it's safe to say that he is not going to draw that conclusion over his next 100 days. Or his next 1,000 days in office. Or ever.

For all the talk of the lessons Trump learned in his first 100 days as President, the truth is that Donald Trump is always going to be Donald Trump. He's not going to change in any meaningful ways.

The reason Trump read from "The Snake" as a candidate is because it worked to rev up his voters. That's the same reason he read from it Saturday night. And the reason he will keep citing it and using other inflammatory rhetoric: Because it works.

There is no "new" or "other" Donald Trump. What you saw in the first 100 days is what he will be in his next 1,000 days.