I'm where yesterday follows today and tomorrow is in the middle. What am I?

Common Wrong Answers
“Time”
Time is linear and does not rearrange days; yesterday, today, and tomorrow are not found in a specific order in time.
“Calendar”
A calendar organizes days in a straightforward sequence and does not place yesterday after today.
“Clock”
A clock measures time but does not represent the concept where yesterday follows today; it shows the current time.
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