Modifies the given dictionary $d$ by adding another key:value assignment for all employees but with a bonus for the next year. You can assume the previous year exists in the dictionary.

Preconditions and Postconditions

d: dict

bonus: int$/$float

year: int

Returns: dict $$ adds the key:value pair with bonus applied

Recommended methods:

dict.keys$(),$ returns all the keys in a dictionary

'one': $1,$ 'two': $2,$ 'three':$3,$ 'four':$4\})$

D$.$keys$()$ returns $[\text{'}$one$\text{'},$ 'two', 'three', 'four'$]$

List concatenation $(+)$ or append method

Tip: Dictionaries, just like lists, are mutable, so saving a reference to a dictionary, say $x=d[2020],$ mapping $x$ to another key in $d$ and then changing information in $x,$ will also change the data in $d[2020],$ which is not a desirable behavior. When adding a new key, create new dictionaries and lists and populate them with the required data.