title: similarity of genes given gene name, in BioPython
body: <p>How can I find the similarity of two genes, given the gene name? 
  By similarity, I think I mean the similarity of the sequences. I am new to this area and given this work by my professor. I do not know many types of similarity</p>
  
  <p>Hopefully, can this be done with Biopython?    </p>
  
  <p>Thank you so much.</p>
  
  <p>Update as response:<br>
  Thanks. But I tried.<br>
  My main problem is when I retrieve gene sequence from database, some results come as a sequence of gene, others come out as a sequence of proteins. I think if we want to compare them, I need make sure they are all gene sequences or they are all protein sequences right?   </p>
  
  <p>Here is the code I use:    </p>
  
  <pre><code> handle = Entrez.efetch(db="nucleotide", id=t ,rettype="gb")
   record = handle.read()
  </code></pre>
  
  <p>Then, for some ids, I got a sequence of <code>agtc</code>, others I got a sequence like <code>mwvllvffll tltylfwpkt</code>. They are proteins right?    </p>
  
  <p>I got stuck here and I do not know what to do next. </p>