title: Why does ï»¿ appear in my data?
body: <p>I downloaded the file 'pi_million_digits.txt' from here:</p>
  
  <p><a href="https://github.com/ehmatthes/pcc/blob/master/chapter_10/pi_million_digits.txt" rel="nofollow noreferrer">https://github.com/ehmatthes/pcc/blob/master/chapter_10/pi_million_digits.txt</a></p>
  
  <p>I then used this code to open and read it:</p>
  
  <pre><code>filename = 'pi_million_digits.txt'
  
  with open(filename) as file_object:
      lines = file_object.readlines()
  
  pi_string = ''
  for line in lines:
      pi_string += line.strip()
  
  print(pi_string[:52] + "...")
  print(len(pi_string))
  </code></pre>
  
  <p>However the output produced is correct apart from the fact it is preceded by same strange symbols: "ï»¿3.141...."</p>
  
  <p>What causes these strange symbols? I am stripping the lines so I'd expect such symbols to be removed.</p>