Split a string into a list of unique words

Design a function (mySplit) that gets a string and returns a list of all its words in lowercase. The returned list must not contain repeating words. You can’t use Python’s default split. For example, with the string:

>>> mySplit('A phrase made up of words. Another phrase with other words.')
    ['a', 'phrase', 'made', 'up', 'of', 'words', 'another', 'with', 'other']
>>> mySplit('Hi! Helloooo HI')
    ['hi', 'helloooo']

To design your set of tests that you have to run automatically with pytest, think about these cases:

• the string is empty

• the string has punctuation marks, like ,;.:-¿?+*()!¡

• the string ends with a point

• the string does not end with a point

• the string has numbers

• que the string has repeated words, but some are capitalized and some are not (for example: 'HEllo hello heLlo'

• the string has more than 1 space between words

• etc.