title: IOError: [Errno 2] No such file or directory, even though the file is existed
body: <p>I am trying to figure out why I am having such error. I ran the same exact code for another directory which contains four files and it is working just fine. This time with using another directory I am getting error this error</p>
  
  <pre><code>IOError: [Errno 2] No such file or directory:
  </code></pre>
  
  <p>even though the files existed. Here is the code which works fine for one directory but not the other one both directory exists and so their four files</p>
  
  <p>The error at line:"with open((file_name),'r') as f:"</p>
  
  <pre><code>import sys,csv,os
  d_files = {}
  def Readfile(file_name):
      d_files[file_name] = []
      print "file_name", file_name # printing the right name 
      with open((file_name),'r') as f:
               reader=csv.reader((f),delimiter='\t')
               for row in reader:
                d_files[file_name].append(row)
  print
  try:
      folder_input = raw_input("Please enter you folder name containing 4 files:   ")
  except Name_Error:
      pass
  for root,dirs,files in os.walk(folder_input):
  for file in files:
      print "file",file  # the right file name 
      pathname=os.path.join(root,file)
      print "DIR:  ",pathname  # right directory inputted 
      print "Now, the file is being parsed"
      Readfile(file)
      print "Now, file", file, "is done parsed"
      print
  </code></pre>
  
  <p>The user will type the path of the four files and which I tested for one directory and it worked but not for the other directory which I am 100% sure that the path is correct and the files exist.</p>
  
  <p>Thanks a lot in advance</p>