Proofs

• expression state at time 25 = "call_function_begin"
• parent stack at time 25 = [ ]
• the expression at time 25 = {"ES": "Estonia", "MX": "Mexico"}

then expression state at time 26 = "end_expr"

• expression state at time 25 = "call_function_begin"
• Value Stack at time 25 = [ [ entry "MX": "Mexico", [ entry "ES": "Estonia", [ ] ] ], [ ] ]
• the expression at time 25 = {"ES": "Estonia", "MX": "Mexico"}

then Value Stack at time 26 = [ ]

• expression state at time 25 = "call_function_begin"
• arguments stack at time 25 = [ ]

then arguments stack at time 26 = [ ]

• expression state at time 25 = "call_function_begin"
• parent stack at time 25 = [ ]

then parent stack at time 26 = [ ]

• expression state at time 25 = "call_function_begin"
• Control Map at time 25 = [ ]

then Control Map at time 26 = [ ]

• expression state at time 25 = "call_function_begin"
• Variables Map at time 25 = [ ]

then Variables Map at time 26 = [ ]

• expression state at time 25 = "call_function_begin"
• the line at time 25 = 1

then the line at time 26 = 1

• expression state at time 25 = "call_function_begin"
• the tab at time 25 = 0

then the tab at time 26 = 0

• expression state at time 25 = "call_function_begin"
• stack at time 25 = [ ]

then stack at time 26 = [ ]

• expression state at time 25 = "call_function_begin"
• Class Map at time 25 = [ ]

then Class Map at time 26 = [ ]

• the line at time 26 = 1
• the tab at time 26 = 0
• statement at line 1, tab 0 = locations = {"ES": "Estonia", "MX": "Mexico"}
• expression state at time 26 = "end_expr"
• Variables Map at time 26 = [ ]
• Return Value at time 26 = Python reference 0

then Variables Map at time 27 = [ entry locations: (Python reference 0), [ ] ]

• the line at time 26 = 1
• the tab at time 26 = 0
• statement at line 1, tab 0 = locations = {"ES": "Estonia", "MX": "Mexico"}
• expression state at time 26 = "end_expr"

then the line at time 27 = 2

• the line at time 26 = 1
• the tab at time 26 = 0
• statement at line 1, tab 0 = locations = {"ES": "Estonia", "MX": "Mexico"}
• expression state at time 26 = "end_expr"

then the tab at time 27 = 0

• the line at time 26 = 1
• the tab at time 26 = 0
• statement at line 1, tab 0 = locations = {"ES": "Estonia", "MX": "Mexico"}
• expression state at time 26 = "end_expr"
• Python Object Store at time 26 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

then Python Object Store at time 27 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

• the line at time 26 = 1
• the tab at time 26 = 0
• statement at line 1, tab 0 = locations = {"ES": "Estonia", "MX": "Mexico"}
• stack at time 26 = [ ]
• expression state at time 26 = "end_expr"

then stack at time 27 = [ ]

• the line at time 26 = 1
• the tab at time 26 = 0
• statement at line 1, tab 0 = locations = {"ES": "Estonia", "MX": "Mexico"}
• Control Map at time 26 = [ ]

then Control Map at time 27 = [ ]

• the line at time 26 = 1
• the tab at time 26 = 0
• statement at line 1, tab 0 = locations = {"ES": "Estonia", "MX": "Mexico"}
• Class Map at time 26 = [ ]

then Class Map at time 27 = [ ]

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"

then the expression at time 28 = __setitem__(locations, "ES", "Spain")

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"

then expression state at time 28 = "begin_expr"

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"

then the line at time 28 = 2

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"

then the tab at time 28 = 0

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"

then Value Stack at time 28 = [ ]

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"

then parent stack at time 28 = [ ]

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"

then arguments stack at time 28 = [ ]

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"
• Python Object Store at time 27 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

then Python Object Store at time 28 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• expression state at time 27 = "not_expr"
• Control Map at time 27 = [ ]

then Control Map at time 28 = [ ]

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• Variables Map at time 27 = [ entry locations: (Python reference 0), [ ] ]

then Variables Map at time 28 = [ entry locations: (Python reference 0), [ ] ]

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• stack at time 27 = [ ]

then stack at time 28 = [ ]

• the line at time 27 = 2
• the tab at time 27 = 0
• statement at line 2, tab 0 = __setitem__(locations, "ES", "Spain")
• Class Map at time 27 = [ ]

then Class Map at time 28 = [ ]

• expression state at time 28 = "begin_expr"
• the expression at time 28 = __setitem__(locations, "ES", "Spain")
• Value Stack at time 28 = [ ]

then Value Stack at time 29 = [ [ ], [ ] ]

• expression state at time 28 = "begin_expr"
• the expression at time 28 = __setitem__(locations, "ES", "Spain")
• parent stack at time 28 = [ ]

then parent stack at time 29 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

• expression state at time 28 = "begin_expr"
• the expression at time 28 = __setitem__(locations, "ES", "Spain")
• arguments stack at time 28 = [ ]

then arguments stack at time 29 = [ [ locations, [ "ES", [ "Spain", [ ] ] ] ], [ ] ]

• expression state at time 28 = "begin_expr"
• the expression at time 28 = __setitem__(locations, "ES", "Spain")

then expression state at time 29 = "iterate_args"

• expression state at time 28 = "begin_expr"
• the expression at time 28 = __setitem__(locations, "ES", "Spain")

then the expression at time 29 = __setitem__(locations, "ES", "Spain")

• expression state at time 28 = "begin_expr"
• Variables Map at time 28 = [ entry locations: (Python reference 0), [ ] ]

then Variables Map at time 29 = [ entry locations: (Python reference 0), [ ] ]

• expression state at time 28 = "begin_expr"
• the line at time 28 = 2

then the line at time 29 = 2

• expression state at time 28 = "begin_expr"
• the tab at time 28 = 0

then the tab at time 29 = 0

• expression state at time 28 = "begin_expr"
• stack at time 28 = [ ]

then stack at time 29 = [ ]

• expression state at time 28 = "begin_expr"
• Python Object Store at time 28 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

then Python Object Store at time 29 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

• expression state at time 28 = "begin_expr"
• Control Map at time 28 = [ ]

then Control Map at time 29 = [ ]

• expression state at time 28 = "begin_expr"
• Class Map at time 28 = [ ]

then Class Map at time 29 = [ ]

• expression state at time 29 = "iterate_args"
• arguments stack at time 29 = [ [ locations, [ "ES", [ "Spain", [ ] ] ] ], [ ] ]

then the expression at time 30 = locations

• expression state at time 29 = "iterate_args"
• arguments stack at time 29 = [ [ locations, [ "ES", [ "Spain", [ ] ] ] ], [ ] ]

then arguments stack at time 30 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]

• expression state at time 29 = "iterate_args"
• arguments stack at time 29 = [ [ locations, [ "ES", [ "Spain", [ ] ] ] ], [ ] ]

then expression state at time 30 = "begin_expr"

• expression state at time 29 = "iterate_args"
• arguments stack at time 29 = [ [ locations, [ "ES", [ "Spain", [ ] ] ] ], [ ] ]
• parent stack at time 29 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

then parent stack at time 30 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

• expression state at time 29 = "iterate_args"
• Value Stack at time 29 = [ [ ], [ ] ]

then Value Stack at time 30 = [ [ ], [ ] ]

• expression state at time 29 = "iterate_args"
• the line at time 29 = 2

then the line at time 30 = 2

• expression state at time 29 = "iterate_args"
• the tab at time 29 = 0

then the tab at time 30 = 0

• expression state at time 29 = "iterate_args"
• stack at time 29 = [ ]

then stack at time 30 = [ ]

• expression state at time 29 = "iterate_args"
• Python Object Store at time 29 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

then Python Object Store at time 30 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

• expression state at time 29 = "iterate_args"
• Control Map at time 29 = [ ]

then Control Map at time 30 = [ ]

• expression state at time 29 = "iterate_args"
• Variables Map at time 29 = [ entry locations: (Python reference 0), [ ] ]

then Variables Map at time 30 = [ entry locations: (Python reference 0), [ ] ]

• expression state at time 29 = "iterate_args"
• Class Map at time 29 = [ ]

then Class Map at time 30 = [ ]

• expression state at time 30 = "begin_expr"
• Variables Map at time 30 = [ entry locations: (Python reference 0), [ ] ]

then Variables Map at time 31 = [ entry locations: (Python reference 0), [ ] ]

• the expression at time 30 = locations
• expression state at time 30 = "begin_expr"
• locations is a variable
• parent stack at time 30 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

then expression state at time 31 = "return"

• the expression at time 30 = locations
• expression state at time 30 = "begin_expr"
• locations is a variable
• Value Stack at time 30 = [ [ ], [ ] ]

then Value Stack at time 31 = [ [ ], [ ] ]

• the expression at time 30 = locations
• expression state at time 30 = "begin_expr"
• locations is a variable
• arguments stack at time 30 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]

then arguments stack at time 31 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]

• expression state at time 30 = "begin_expr"
• the expression at time 30 = locations
• locations is a variable
• Variables Map at time 30 = [ entry locations: (Python reference 0), [ ] ]

then Return Value at time 31 = Python reference 0

• expression state at time 30 = "begin_expr"
• the expression at time 30 = locations
• locations is a variable
• parent stack at time 30 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

then parent stack at time 31 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

• expression state at time 30 = "begin_expr"
• the line at time 30 = 2

then the line at time 31 = 2

• expression state at time 30 = "begin_expr"
• the tab at time 30 = 0

then the tab at time 31 = 0

• expression state at time 30 = "begin_expr"
• stack at time 30 = [ ]

then stack at time 31 = [ ]

• expression state at time 30 = "begin_expr"
• Python Object Store at time 30 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

then Python Object Store at time 31 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

• expression state at time 30 = "begin_expr"
• Control Map at time 30 = [ ]

then Control Map at time 31 = [ ]

• expression state at time 30 = "begin_expr"
• Class Map at time 30 = [ ]

then Class Map at time 31 = [ ]

• expression state at time 31 = "return"
• Value Stack at time 31 = [ [ ], [ ] ]
• Return Value at time 31 = Python reference 0

then Value Stack at time 32 = [ [ Python reference 0, [ ] ], [ ] ]

• expression state at time 31 = "return"
• Variables Map at time 31 = [ entry locations: (Python reference 0), [ ] ]

then Variables Map at time 32 = [ entry locations: (Python reference 0), [ ] ]

• expression state at time 31 = "return"
• the line at time 31 = 2

then the line at time 32 = 2

• expression state at time 31 = "return"
• the tab at time 31 = 0

then the tab at time 32 = 0

• expression state at time 31 = "return"
• arguments stack at time 31 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]

then arguments stack at time 32 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]

• expression state at time 31 = "return"
• parent stack at time 31 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

then parent stack at time 32 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

• expression state at time 31 = "return"
• stack at time 31 = [ ]

then stack at time 32 = [ ]

• expression state at time 31 = "return"
• Class Map at time 31 = [ ]

then Class Map at time 32 = [ ]

• expression state at time 31 = "return"
• Python Object Store at time 31 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

then Python Object Store at time 32 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

• expression state at time 31 = "return"
• Control Map at time 31 = [ ]

then Control Map at time 32 = [ ]

• expression state at time 32 = "iterate_args"
• arguments stack at time 32 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]

then the expression at time 33 = "ES"

• expression state at time 32 = "iterate_args"
• arguments stack at time 32 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]

then arguments stack at time 33 = [ [ "Spain", [ ] ], [ ] ]

• expression state at time 32 = "iterate_args"
• arguments stack at time 32 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]

then expression state at time 33 = "begin_expr"

• expression state at time 32 = "iterate_args"
• arguments stack at time 32 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]
• parent stack at time 32 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

then parent stack at time 33 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

• expression state at time 32 = "iterate_args"
• Value Stack at time 32 = [ [ Python reference 0, [ ] ], [ ] ]

then Value Stack at time 33 = [ [ Python reference 0, [ ] ], [ ] ]

• expression state at time 32 = "iterate_args"
• the line at time 32 = 2

then the line at time 33 = 2

• expression state at time 32 = "iterate_args"
• the tab at time 32 = 0

then the tab at time 33 = 0

• expression state at time 32 = "iterate_args"
• stack at time 32 = [ ]

then stack at time 33 = [ ]

• expression state at time 32 = "iterate_args"
• Python Object Store at time 32 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

then Python Object Store at time 33 = [ {"ES": "Estonia", "MX": "Mexico"}, [ ] ]

• expression state at time 32 = "iterate_args"
• Control Map at time 32 = [ ]

then Control Map at time 33 = [ ]

• expression state at time 32 = "iterate_args"
• Variables Map at time 32 = [ entry locations: (Python reference 0), [ ] ]

then Variables Map at time 33 = [ entry locations: (Python reference 0), [ ] ]

• expression state at time 32 = "iterate_args"
• Class Map at time 32 = [ ]

then Class Map at time 33 = [ ]

• the expression at time 33 = "ES"
• expression state at time 33 = "begin_expr"
• "ES" is constant
• parent stack at time 33 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

then expression state at time 34 = "return"

• the expression at time 33 = "ES"
• expression state at time 33 = "begin_expr"
• "ES" is constant
• Value Stack at time 33 = [ [ Python reference 0, [ ] ], [ ] ]

then Value Stack at time 34 = [ [ Python reference 0, [ ] ], [ ] ]

• the expression at time 33 = "ES"
• expression state at time 33 = "begin_expr"
• "ES" is constant
• arguments stack at time 33 = [ [ "Spain", [ ] ], [ ] ]

then arguments stack at time 34 = [ [ "Spain", [ ] ], [ ] ]

• expression state at time 33 = "begin_expr"
• the expression at time 33 = "ES"
• "ES" is constant

then Return Value at time 34 = "ES"

• expression state at time 33 = "begin_expr"
• the expression at time 33 = "ES"
• "ES" is constant
• parent stack at time 33 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

then parent stack at time 34 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

• expression state at time 33 = "begin_expr"
• the line at time 33 = 2

then the line at time 34 = 2

• expression state at time 33 = "begin_expr"
• the tab at time 33 = 0

then the tab at time 34 = 0

• expression state at time 33 = "begin_expr"
• stack at time 33 = [ ]

then stack at time 34 = [ ]