if the following are true:

• the line at time 45 = 3
• the tab at time 45 = 1
• statement at line 3, tab 1 = a = __add__(a, 1)
• expression state at time 45 = "end_expr"
• Variables Map at time 45 = [ entry a: 1, [ ] ]
• Return Value at time 45 = 2

then Variables Map at time 46 = [ entry a: 2, [ ] ]

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