method
strptime

strptime(str='-4712-01-01T00:00:00+00:00', fmt='%FT%T%z', sg=ITALY)
public
Create a new DateTime object by parsing from a String according to a specified format.
str is a String holding a date-time representation. fmt is the format that the date-time is in. See date/format.rb for details on supported formats.
The default str is ā-4712-01-01T00:00:00+00:00ā, and the default fmt is ā%FT%T%zā. This gives midnight on Julian Day Number day 0.
sg specifies the Day of Calendar Reform.
An ArgumentError will be raised if str cannot be parsed.