title: How to fix a syntax error when it says invalid character in identifier
body: <p>I just began to learn python and there is a syntax error which I can not fix when I doing my latest project.</p>
  
  <pre><code>def adding_report():
      report_value = input('Input an integer to add to the total or "Q" to quit: ')
      while True:
          if report_value == "":
              report_value = input('Input an integer to add to the total or "Q" to quit: ')
          elif report_value.isdigit()：
              final_value = int(report_value) + int(report_value)
          elif report_value.lower() == "q"
              break
  adding_report()
  </code></pre>
  
  <p>I expect this function can run and ask me for an integer to add to the report until I enter a 'Q' which can break the loop, then a result showing  the final value of  the report would appear but there is a syntax error when I run this code.</p>
  
  <pre><code>elif report_value.isdigit()：
                             ^
  SyntaxError: invalid character in identifier
  </code></pre>