title: How can I add characters before and after each ID in this array?
body: <p>I scraped and collected IDs from the Japanese horse racing information site. The array of ID is stored as a NumPy array. How can I add characters before and after each ID in this array?</p>
  <pre><code>import numpy as np
  
  a = np.array([2019104896, 2016102929, 2018105085]) 
  print(a) # [2019104896 2016102929 2018105085]
  print(type(a)) # &lt;class 'numpy.ndarray'&gt;
  b = a.astype(str)
  c = &quot;\n&quot;.join(b) # new line 
  with open('horse_id.txt', 'w') as f: # make a text file
      f.write(c)
  </code></pre>
  <p>By executing the above code, I got the following text file.</p>
  <pre><code>horse_id.text
  2019104896
  2016102929
  2018105085
  </code></pre>
  <p>I'd like to add characters before and after each ID like this:</p>
  <pre><code>'https://db.netkeiba.com/horse/' + ID + '/'
  </code></pre>
  <p>What I want to create is the following text file</p>
  <pre><code>horse_id.txt
  https://db.netkeiba.com/horse/2019104896/
  https://db.netkeiba.com/horse/2016102929/
  https://db.netkeiba.com/horse/2018105085/
  </code></pre>
  <p>How can i achieve that?</p>