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.
The Graying Process. With age, the pigment cells in a hair follicle gradually die off. As they do, that strand of hair will no longer grow in with as much color and will show up as more silver, gray or white as it continues to grow.Eventually, if all the pigment cells die, the hair grows in completely gray.he Graying Process. With age, the pigment cells in a hair follicle gradually die off. As they do, that strand of hair will no longer grow in with as much color and will show up as more silver, gray or white as it continues to grow.