parse_dt method that specifically returns a DateTime #917

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Feature Request

pdl.parse can return a Date, Time, Duration, or DateTime, depending on the args you pass to it. This is annoying in type-checked codebases, because you have to write

my_dt = pdl.parse(my_dt_string)
assert isinstance(my_dt, pdl.DateTime)

every time you want to parse a datetime string.

I wish there were a function parse_dt that was guaranteed to return a DateTime, and raises if you pass it something else like '2024-09-12T10:00:00Z/2024-09-12T15:30:00Z'.