Tokenize a string with escaping

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Write a function or program that can split a string at each non-escaped occurrence of a separator character.

It should accept three input parameters:

• The string
• The separator character
• The escape character

It should output a list of strings.

Rules for splitting:

• The fields that were separated by the separators, become the elements of the output list.
• Empty fields should be preserved, even at the start and end.

Rules for escaping:

• "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself.
• When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special).
• Each occurrences of the escape character that was used to escape something, should not become part of the output.

Demonstrate that your function satisfies the following test-case:

Given the string

one^|uno||three^^^^|four^^^|^cuatro|

and using | as a separator and ^ as escape character, your function should output the following array:

['one|uno', '', 'three^^', 'four^|cuatro', '']