title: Wrong indentation in python interpreter after customising interpreter prompts
body: <p>I have recently made a <code>usercustomised.py</code> file as described here (<a href="https://docs.python.org/2/tutorial/appendix.html" rel="nofollow noreferrer">https://docs.python.org/2/tutorial/appendix.html</a>), which colors my <code>sys.ps1</code> and <code>sys.ps2</code> attributes as so:</p>
  
  <pre><code>import sys
  
  sys.ps1 = "\033[1;33m&gt;&gt;&gt;\033[0m "
  sys.ps2 = "\033[1;36m...\033[0m "
  </code></pre>
  
  <p>and added the following line to my <code>~/.bashrc</code> file:</p>
  
  <pre><code>export PYTHONSTARTUP="*path_to*/usercustomised.py" 
  </code></pre>
  
  <p>However, this has now broken the indentation in my python interpreter. Instead of using continuous indents of char size 4, the interpreter now uses one tab of size 1, and another of size 7. For example:</p>
  
  <pre><code>&gt;&gt;&gt; for a in A:
  ...  if line 1:
  ...         line 2
  </code></pre>
  
  <p>instead of </p>
  
  <pre><code>&gt;&gt;&gt; for a in A:
  ...     if line 1:
  ...         line 2
  </code></pre>
  
  <p>When I comment out the appropriate line in my <code>~/.bashrc</code> file, the interpreter returns to normal with the correct indenting (but now uncoloured, which I don't particularly want). </p>
  
  <p>What is going on? I am using WSL and python 3.7.</p>