Update README

Author: mdbrnowski

README.md

@@ -2,6 +2,25 @@
 
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+> [!IMPORTANT]
+> Python is known to be slow. This language has an interpreter *written in Python*. It will be *very* slow. Apart from providing nice syntax for matrices and tensors, it has absolutely nothing to offer; sorry about that.
+
 To see all available commands, simply run `./main.py`.
 
 I'm afraid you'll need to explore the language on your own, since I haven't had the time to write anything resembling proper documentation.
+
+Here is a sample of code:
+
+```
+a = 0;
+b = 1;
+n = 10000;
+while (a < n) {
+    print a;
+    temp = a;
+    a = b;
+    b += temp;
+}
+```
+
+For more, you can browse [tests](./tests).