title: empty files in python
body: <p>I am trying to create a file with all the magnetic information in my lists. I've used this code before as well. for some reason the file it returns is empty. I'm not sure why.</p>
  
  <p>here is my code:</p>
  
  <pre><code>magnetosheath_Bx = JSS_Bx[12339:13795]
  magnetosheath_By = JSS_By[12339:13795]
  magnetosheath_Bz = JSS_Bz[12339:13795]        
  magnetosheath_B = JSS_Bmag[12339:13795]
  magnetosheath_time = epochtime_magdata[12339:13795]
  magnetosheath_r = new_RJSE[12339:13795]   
  
  Magnetosheath_data = zip(magnetosheath_Bx, magnetosheath_By, magnetosheath_Bz, magnetosheath_B, magnetosheath_time, magnetosheath_r)
  
  
  filenew= open('Ulysses_Magnetoseath.txt' , 'w') 
  
  filenew.write("hello")
  for magnetic_data in Magnetosheath_data:
          filenew.write('{}   {}  {}  {}  {}  {}\n'.format(magnetic_data[0], magnetic_data[1], magnetic_data[2], magnetic_data[3],magnetic_data[4],magnetic_data[5] ))
          filenew.write("hello")
  </code></pre>