title: How to change the sign of z3py negated inequalities
body: <p>Let's say I have the following z3py expression:</p>
  <pre><code>import z3
  x, y = z3.Ints(&quot;x y&quot;)
  z3_expression = z3.Not(x&lt;y)
  </code></pre>
  <p>This expression is saved and printed with <code>str()</code> as <code>Not(x &lt; y)</code>. I want to know if there is any way to apply that <code>Not()</code> operator to the expression and change the sign of the inequality, i.e. I want to remove that negation operator and make the expression look like this: <code>z3_expression = (x &gt;= y)</code>, the parenthesis is not neccesary, I just put it to make it clearer.</p>
  <p>Is there a way to do it preferably using z3py?</p>
  <p><strong>EDIT:</strong>
  The first answear solves this concrete problem, but if I change the expression to:</p>
  <pre><code>z3_expression = z3.Not(x&lt;=y)
  z3_simplified_expression = z3.simplify(z3_expression)
  print(z3_simplified_expression)
  </code></pre>
  <p>This prints:</p>
  <pre><code>Not(x &lt;= y)
  </code></pre>
  <p>Instead of:</p>
  <pre><code>x &gt; y
  </code></pre>