text: #!/Library/Frameworks/Python.framework/Versions/3.6/bin/python3
  
  """
  	References for handling the "__file__" attribute.
  	+ https://stackoverflow.com/questions/9271464/what-does-the-file-variable-mean-do
  """
  
  
  import os
  
  print("= Perform split() operation.")
  path_prefix, last_pathname_component = os.path.split('/my/path/to/whatever/somefile.ext')
  print(path_prefix)
  print(last_pathname_component)
  
  print("= Perform splitext() operation.")
  filename, file_extension = os.path.splitext('/some/path/to/somefile.ext')
  print(filename)
  print(file_extension)
  
  print("= Perform splitext() operation again.")
  filename, file_extension = os.path.splitext('fosca.battati')
  print(filename)
  print(file_extension)
  
  
  print("= Perform splitext() operation yet another time.")
  filename, file_extension = os.path.splitext('daniela-stefanescu')
  print(filename)
  print(file_extension)
  
  
  
  print("= Perform splitext() operation on multiple file extensions.")
  filename, file_extension = os.path.splitext('ansu_mani.tar.gz')
  print(filename)
  print(file_extension)
  f_name, f_extension = os.path.splitext(file_extension)
  print(f_name)
  print(f_extension)
  f_name1, f_extension1 = os.path.splitext(filename)
  print(f_name1)
  print(f_extension1)
  
  
  
  """
  	References and notes:
  	+ \cite[From section "File and Directory Access", subsection "os.path — Common pathname manipulations"]{DrakeJr2016b}
  		Available online from "The Python Standard Library: File and Directory Access: os.path — Common pathname manipulations" at: https://docs.python.org/3/library/os.path.html#os.path.expanduser;
  			February 12, 2020 was the last accessed date.
  		- Information about the "os.path.expanduser(path)" command
  			replaces relative paths starting from the current
  			user's home directory (starting with "~" or "~user").
  			* Hence, if the path does not start with "~" nor
  				"~user", or if the path cannot be expanded,
  				the 'path' remains unchanged.
  	+ \cite[From section "Generic Operating System Services", subsection "os — Miscellaneous operating system interfaces"]{DrakeJr2016b}
  		Available online from "The Python Standard Library: Generic Operating System Services: os — Miscellaneous operating system interfaces" at: https://docs.python.org/3/library/os.html#os.getcwd;
  		February 12, 2020 was the last accessed date.
  	+ [Dias2016] Russell Dias and Mark Amery, Answer to "Find current
  		directory and file's directory [duplicate]", from
  		Stack Exchange Inc.: Stack Overflow: Questions,
  		Stack Exchange, Inc., New York, NY, July 31, 2016.
  		Available online from Stack Exchange Inc.: Stack
  			Overflow: Questions at: https://stackoverflow.com/a/5137509/1531728 and https://stackoverflow.com/questions/5137497/find-current-directory-and-files-directory/5137509#5137509;
  			February 12, 2020 was the last accessed date.
  	+ John Howard and Mark Amery, "Find current
  		directory and file's directory [duplicate]", from
  		Stack Exchange Inc.: Stack Overflow: Questions,
  		Stack Exchange, Inc., New York, NY, July 31, 2016.
  		Available online from Stack Exchange Inc.: Stack
  			Overflow: Questions at: https://stackoverflow.com/q/5137497/1531728 and https://stackoverflow.com/questions/5137497/find-current-directory-and-files-directory
  			February 12, 2020 was the last accessed date.
  """
  valid_path = os.path.expanduser("./")
  print("valid_path is:",valid_path,"=")
  """
  	See \cite[From section "File and Directory Access", subsection "os.path — Common pathname manipulations"]{DrakeJr2016b}
  		for reasons why the "os.path.expanduser(path)" command
  		does not work with the paths "./" nor ".".
  """
  valid_path = os.path.expanduser(".")
  print("New valid_path is:",valid_path,"=")
  """
  	See \cite[From section "Generic Operating System Services", subsection "os — Miscellaneous operating system interfaces"]{DrakeJr2016b}.
  """
  current_wking_dir = os.getcwd()
  print("New current_wking_dir is:",current_wking_dir,"=")
  
  # \cite{Dias2016}
  full_path = os.path.realpath("./")
  print("full_path is:",full_path,"=")
  full_path = os.path.realpath(".")
  print("Now full_path is:",full_path,"=")
  
  absolute_path = os.path.abspath("./")
  print("absolute_path is:",absolute_path,"=")
  absolute_path = os.path.abspath(".")
  print("Now absolute_path is:",absolute_path,"=")
  
  
  """
  	Get the name of the current directory, and the path
  		to the current directory.
  	Reference:
  	+ StormShadow, Answer to "Find current directory and file's directory [duplicate]," Stack Exchange Inc., New York, NY, October 9, 2013.
  		Available online from Stack Exchange Inc.: Stack Overflow: Questions at: https://stackoverflow.com/a/19269546/1531728 and https://stackoverflow.com/questions/5137497/find-current-directory-and-files-directory/19269546#19269546
  			February 13, 2020 was the last accessed date.
  """
  current_folder_path, current_folder_name = os.path.split(os.getcwd())
  print("current_folder_path is:",current_folder_path,"=")
  print("current_folder_name is:",current_folder_name,"=")
  
  
  
  
  
  absolute_path_to_store_results = "/Users/zhiyang/Documents/ricerca/risultati_sperimentali/std-cell-library-characterization"
  
  print("=	Valid path, existent file.")
  path_to_file = "/Users/zhiyang/Documents/ricerca/risultati_sperimentali/std-cell-library-characterization/2020/february/7-2-2020-9-56-54-334414.txt"
  if path_to_file is not None:
  	print("	path_to_file is not None")
  if os.path.exists(path_to_file):
  	print("	os.path.exists(path_to_file)")
  if os.path.isfile(path_to_file):
  	print("	os.path.isfile(path_to_file)")
  if path_to_file.startswith(absolute_path_to_store_results):
  	print("	path_to_file.startswith(absolute_path_to_store_results)")
  
  
  print("=	Valid path, non-existent file.")
  path_to_file = "/Users/zhiyang/Documents/ricerca/risultati_sperimentali/std-cell-library-characterization/2020/random.rnd"
  if path_to_file is not None:
  	print("	path_to_file is not None")
  if os.path.exists(path_to_file):
  	print("	os.path.exists(path_to_file)")
  if os.path.isfile(path_to_file):
  	print("	os.path.isfile(path_to_file)")
  if path_to_file.startswith(absolute_path_to_store_results):
  	print("	path_to_file.startswith(absolute_path_to_store_results)")