default character encoding in some machines with Win OS causes crash!

[Omar Rashad]

PR#58

The bug is actually easy to fix but causes the whole code to collapse.

Details

file i/o `open()` function have `encoding` argument that by default is set to the machine's default character encoding.

• Most Linux machines uses utf-8 as default encoding which is ok with most languages characters, emojis and symbols.

• In Windows machines, a big portion of them uses cp1252 as default encoding which is very limited:
  

---

open() docs: "if encoding is not specified the encoding used is platform dependent" see

• Reproducing the bug
  
  _{(as you see even if user didn't send any invalid characters, GPT sending one invalid character is enough to cause the bug)}

• Fix
  simply assigning open( , encoding= "utf-8") for all systems or detecting the system encoding first using:

import locale
sys_char_encoding = locale.getpreferredencoding()
#rest of the code

[Marco Lardera]

Thank you @orsnaro for catching this bug affecting Windows machines, I merged your fix...