title: Binary search tree insertion Python
body: <p>What is wrong with my insert function? I'm passing along the <code>tr</code> and the element <code>el</code> that I wish to insert, but I keep getting errors...</p>
  
  <pre><code>def insert( tr,el ):
      """ Inserts an element into a BST -- returns an updated tree """
      if tr == None:
          return createEyecuBST( el,None )
      else:
          if el &gt; tr.value:
              tr.left = createEyecuBST( el,tr )
          else:
              tr.right = createEyecuBST( el,tr )
          return EyecuBST( tr.left,tr.right,tr)
  </code></pre>
  
  <p>Thanks in advance.</p>
  
  <p>ERROR:</p>
  
  <hr>
  
  <pre><code>ValueError: Not expected BST with 2 elements
  </code></pre>
  
  <p>It's a test function that basically tells me whether or not what I'm putting in is what I want out.</p>