Python 3 UnicodeEncodeError: codec 'ascii' cannot encode characters

Question

I was just starting to learn Python, but I already ran into problems.
I have a simple script with only one command:

#!/usr/bin/env python3
print("Příliš žluťoučký kůň úpěl ďábelské ódy.") # Text in Czech 

When I try to run this script:

python3 hello.py 

I get this message:

Traceback (most recent call last):
  File "hello.py", line 2, in <module>
    print("P\u0159\xedli\u0161 \u017elu\u0165ou\u010dk\xfd k\u016fn \xfap\u011bl \u010f\xe1belsk\xe9 \xf3dy.")
UnicodeEncodeError: 'ascii' codec can't encode characters in position 1-2: ordinal not in range(128)

I am using Kubuntu 16.04 and Python 3.5.2. When I tried it: export PYTHONIOENCODING=utf-8It worked, but only temporarily. The next time I opened bash, I got the same error.

According to https://docs.python.org/3/howto/unicode.html#the-string-type , the default encoding for Python source code is UTF-8.
Thus, I have the source file with the saved UTF-8 identifier, Konsole is installed in UTF-8, but I still get the error!
Even if I add

# -*- coding: utf-8 -*-

.

: , python, python3, . Python 2.7.12, 3.5.2?

- ? .

Answer 1

, , . .
locale, :

LANG=C
LANGUAGE=
LC_CTYPE="C"
LC_NUMERIC=cs_CZ.UTF-8
LC_TIME=cs_CZ.UTF-8
LC_COLLATE=cs_CZ.UTF-8
LC_MONETARY=cs_CZ.UTF-8
LC_MESSAGES="C"
LC_PAPER="C"
LC_NAME="C"
LC_ADDRESS="C"
LC_TELEPHONE="C"
LC_MEASUREMENT=cs_CZ.UTF-8
LC_IDENTIFICATION="C"
LC_ALL=

"C" , charmap ANSI. . locale charmap : ANSI_X3.4-1968, .
, Ubuntu.

/etc/default/locale:

LANGUAGE=cs_CZ.UTF-8
LC_ALL=cs_CZ.UTF-8

( ), .

locale :

LANG=C
LANGUAGE=cs
LC_CTYPE="cs_CZ.UTF-8"
LC_NUMERIC="cs_CZ.UTF-8"
LC_TIME="cs_CZ.UTF-8"
LC_COLLATE="cs_CZ.UTF-8"
LC_MONETARY="cs_CZ.UTF-8"
LC_MESSAGES="cs_CZ.UTF-8"
LC_PAPER="cs_CZ.UTF-8"
LC_NAME="cs_CZ.UTF-8"
LC_ADDRESS="cs_CZ.UTF-8"
LC_TELEPHONE="cs_CZ.UTF-8"
LC_MEASUREMENT="cs_CZ.UTF-8"
LC_IDENTIFICATION="cs_CZ.UTF-8"
LC_ALL=cs_CZ.UTF-8

locale charmap :

UTF-8