Given an number, return a string which contains varying amounts of the word 'MEGA' depending on the given number's order of magnitude.
"not a mega milestone"."MEGA milestone"."MEGA" to the start of the string.See the examples below for further clarification!
how_mega_is_it(54) ➞ "not a mega milestone"
how_mega_is_it(143) ➞ "MEGA milestone"
how_mega_is_it(1000) ➞ "MEGA MEGA milestone"
how_mega_is_it(9999.9) ➞ "MEGA MEGA milestone"
how_mega_is_it(10000) ➞ "MEGA MEGA MEGA milestone"