map (function, iterable, ...) Â¶ Apply function to every item of iterable and return a list of the results. If additional iterable arguments are passed, function must take that many arguments and is applied to the items from all iterables in parallel.
The grey hair ârule of thumbâ is that by the age of 50, half of the population have lost the colour in 50% of their hair. When researchers tested this rule, they found that 74% of people aged between 45 and 65 had grey hair, with an average intensity of 27%.Generally, men have more grey hair than women.he grey hair ârule of thumbâ is that by the age of 50, half of the population have lost the colour in 50% of their hair. When researchers tested this rule, they found that 74% of people aged between 45 and 65 had grey hair, with an average intensity of 27%. Generally, men have more grey hair than women.
Blond children tend to see their hair darken around the age or seven or eight. The mechanism for this is unknown and probably not related to hormones, as the darkening precedes puberty by a number of years. New parents often find the first coat of their babyâs hair is darker than expected. It is not until this first hair is shed and replaced, at around eight to 12 months of age, that you get a clear indication of their hair colour.