UnicodeEncodeError: 'charmap' codec can't encode character '\u2212' in position 439: character maps to <undefined> code example

Example 1: UnicodeDecodeError: 'charmap' codec can't decode byte 0x9d in position 6148: character maps to

Add encoding:
	
	file = open(filename, encoding="utf8")

Example 2: charmap codec can't encode character

with open(filename_csv , 'w', newline='',encoding="utf-8") as csv_file:

Example 3: charmap' codec can't encode character '\u010d' in position 97: character maps to

import io
with io.open(fname, "w", encoding="utf-8") as f:
    f.write(html)

Example 4: UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 92: character maps to

file = open(filename, encoding="cp437")