The localtime() function in the time module converts seconds representing time since  the epoch into local time in form of a struct_time object. A struct_time object contains information about the represented date such as the year, month, day, hour, minute, second, weekday, and day of the year.

localtime(secs = None)
secs An optional arguments representing the seconds to be converted into a local time.

The function returns a struct_time object representing the local time, represented by the given seconds.If the seconds are not given, it returns the current local time.

Using the localtime() function seconds given.

#import time module
import time

#without any argument
now = time.localtime()
print(now)

 Use the localtime() function with seconds given

import time

yesterday= time.localtime(time.time() - 86400)

# Print yesterday's time 
print("Year: ", yesterday.tm_year)
print("Month: ", yesterday.tm_mon)
print("Day: ", yesterday.tm_mday)
print("Hour: ", yesterday.tm_hour)
print("Minute: ", yesterday.tm_min)
print("Second: ", yesterday.tm_sec)

Converting struct_time into a string

We can convert the struct_time object into a formatted more human-friendly date using the strftime() function. 

strftime(format, t = None)
format a string containing the format of the date (e.g. "%d/%m/%Y " for DD/MM/YYYY)
t An optional argument representing the struct_time object we wish to convert. If not given it defaults to the current moment.

Convert struct_time object into a formatted string

import time

#Today's date as a string
today = time.localtime()
formatted_today = time.strftime("%d %b %Y  %I:%M:%S %p", today)
print(formatted_today)

#yesterday's time as a string 
yesterday= time.localtime(time.time() - 86400)
formatted_yesterday = time.strftime("%d %b %Y  %I:%M:%S %p", yesterday)

print(formatted_yesterday)

The following table summarizes some of the formatting parameters. 

parameter description
%a Abbreviated weekday name
%A Full weekday name
%b Abbreviated month name
%B Full month name
%d The day of the month, [0, 31]
%H Hour (24-hour clock) as a decimal number [00,23]
%I Hour (12-hour clock) as a decimal number [01,12]
%j Day of the year as a decimal number [001,366]
%m Month as a decimal number [01,12]
%M Minute as a decimal number [00,59]
%p Locale’s equivalent of either AM or PM
%S Second as a decimal number [00,61]
%U Week number of the year (Sunday as the first day of the week) as a decimal number [00,53]
%w Weekday as a decimal number [0(Sunday),6]
%W Week number of the year (Monday as the first day of the week) as a decimal number [00,53]
%x Date representation.
%X time representation.
%y Year without century, [00 - 99]
%Y Year with century as a decimal number
%z UTC offset in the form +HHMM or -HHMM
%Z Timezone name.