title: virtual environment(ubuntu) NameError: name 'mark' is not defined
body: <p>I am new to Linux. Currently I am using WSL(Ubuntu). In my virtual environment this code does not work, but on online IDE the same code works. I have installed latest version of python into my virtual environment.</p>
  <pre><code>word_one = input(&quot;Enter the first word:&quot;)  #input mark
  word_two = input(&quot;Enter the second word:&quot;) #input mary
  
  # if element
  
  if word_one &gt; word_two:
      print(word_two,word_one)
  
  else:
      print(word_one,word_two)
  </code></pre>
  <p>to execute</p>
  <pre><code>python test.py
  </code></pre>
  <pre><code>Traceback (most recent call last):
    File &quot;test.py&quot;, line 1, in &lt;module&gt;
      word_one = input(&quot;Enter the first word:&quot;)
    File &quot;&lt;string&gt;&quot;, line 1, in &lt;module&gt;
  NameError: name 'mark' is not defined
  </code></pre>
  <p>update:
  even after installing the latest version of python into my virtual environment, it was still running as python2, so whenever I do &quot;python test.py&quot; it was running the python script using old version. To solve this I had to use &quot;python3 test.py&quot; and it was working good.</p>
  <p>Question? <br>
  is there a way where I can make python3 as my default execution, so whenever I type <br>&quot;python test.py&quot; it can run using latest version?</p>