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Doesn't feel worth adding a cross-reference for this section.
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‎episodes/optimisation-using-python.md‎

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@@ -150,134 +150,6 @@ operatorSearch: 28.43ms
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An easy approach to follow is that if two blocks of code do the same operation, the one that contains less Python is probably faster. This won't apply if you're using 3rd party packages written purely in Python though.
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::::::::::::::::::::::::::::::::::::: callout
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### Python bytecode
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You can use `dis` to view the bytecode generated by Python, the amount of byte-code more strongly correlates with how much code is being executed by the Python interpreter. However, this still does not account for whether functions called are implemented using Python or C.
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The pure Python search compiles to 82 lines of byte-code.
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```python
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import dis
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def manualSearch():
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ls = generateInputs()
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ct = 0
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for i in range(0, int(N*M), M):
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for j in range(0, len(ls)):
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if ls[j] == i:
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ct += 1
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break
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dis.dis(manualSearch)
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```
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```output
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11 0 LOAD_GLOBAL 0 (generateInputs)
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2 CALL_FUNCTION 0
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4 STORE_FAST 0 (ls)
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12 6 LOAD_CONST 1 (0)
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8 STORE_FAST 1 (ct)
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13 10 LOAD_GLOBAL 1 (range)
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12 LOAD_CONST 1 (0)
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14 LOAD_GLOBAL 2 (int)
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16 LOAD_GLOBAL 3 (N)
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18 LOAD_GLOBAL 4 (M)
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20 BINARY_MULTIPLY
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22 CALL_FUNCTION 1
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24 LOAD_GLOBAL 4 (M)
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26 CALL_FUNCTION 3
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28 GET_ITER
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>> 30 FOR_ITER 24 (to 80)
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32 STORE_FAST 2 (i)
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14 34 LOAD_GLOBAL 1 (range)
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36 LOAD_CONST 1 (0)
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38 LOAD_GLOBAL 5 (len)
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40 LOAD_FAST 0 (ls)
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42 CALL_FUNCTION 1
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44 CALL_FUNCTION 2
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46 GET_ITER
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>> 48 FOR_ITER 14 (to 78)
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50 STORE_FAST 3 (j)
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15 52 LOAD_FAST 0 (ls)
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54 LOAD_FAST 3 (j)
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56 BINARY_SUBSCR
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58 LOAD_FAST 2 (i)
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60 COMPARE_OP 2 (==)
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62 POP_JUMP_IF_FALSE 38 (to 76)
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16 64 LOAD_FAST 1 (ct)
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66 LOAD_CONST 2 (1)
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68 INPLACE_ADD
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70 STORE_FAST 1 (ct)
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17 72 POP_TOP
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74 JUMP_FORWARD 1 (to 78)
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15 >> 76 JUMP_ABSOLUTE 24 (to 48)
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>> 78 JUMP_ABSOLUTE 15 (to 30)
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13 >> 80 LOAD_CONST 0 (None)
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82 RETURN_VALUE
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```
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Whereas the `in` variant only compiles to 54.
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```python
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import dis
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def operatorSearch():
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ls = generateInputs()
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ct = 0
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for i in range(0, int(N*M), M):
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if i in ls:
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ct += 1
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dis.dis(operatorSearch)
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```
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```output
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4 0 LOAD_GLOBAL 0 (generateInputs)
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2 CALL_FUNCTION 0
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4 STORE_FAST 0 (ls)
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5 6 LOAD_CONST 1 (0)
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8 STORE_FAST 1 (ct)
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6 10 LOAD_GLOBAL 1 (range)
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12 LOAD_CONST 1 (0)
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14 LOAD_GLOBAL 2 (int)
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16 LOAD_GLOBAL 3 (N)
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18 LOAD_GLOBAL 4 (M)
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20 BINARY_MULTIPLY
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22 CALL_FUNCTION 1
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24 LOAD_GLOBAL 4 (M)
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26 CALL_FUNCTION 3
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28 GET_ITER
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>> 30 FOR_ITER 10 (to 52)
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32 STORE_FAST 2 (i)
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7 34 LOAD_FAST 2 (i)
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36 LOAD_FAST 0 (ls)
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38 CONTAINS_OP 0
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40 POP_JUMP_IF_FALSE 25 (to 50)
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8 42 LOAD_FAST 1 (ct)
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44 LOAD_CONST 2 (1)
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46 INPLACE_ADD
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48 STORE_FAST 1 (ct)
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>> 50 JUMP_ABSOLUTE 15 (to 30)
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6 >> 52 LOAD_CONST 0 (None)
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54 RETURN_VALUE
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```
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:::::::::::::::::::::::::::::::::::::::::::::
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## Example: Parsing data from a text file
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‎learners/technical-appendix.md‎

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@@ -6,11 +6,132 @@ The topics covered here exceed the level of knowledge required to benefit from t
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77
**Contents**
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- []()
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- [Viewing Python's ByteCode](#viewing-pythons-bytecode)
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- []()
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- []()
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##
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## Viewing Python's ByteCode
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You can use `dis` to view the bytecode generated by Python, the amount of bytecode more strongly correlates with how much code is being executed by the Python interpreter and hence how long it may take to execute. However, this is a crude proxy as it does not account for whether functions that are called and whether those functions are implemented using Python or C.
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The pure Python search compiles to 82 lines of byte-code.
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```python
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import dis
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def manualSearch():
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ls = generateInputs()
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ct = 0
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for i in range(0, int(N*M), M):
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for j in range(0, len(ls)):
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if ls[j] == i:
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ct += 1
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break
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dis.dis(manualSearch)
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```
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```output
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11 0 LOAD_GLOBAL 0 (generateInputs)
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2 CALL_FUNCTION 0
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4 STORE_FAST 0 (ls)
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12 6 LOAD_CONST 1 (0)
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8 STORE_FAST 1 (ct)
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13 10 LOAD_GLOBAL 1 (range)
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12 LOAD_CONST 1 (0)
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14 LOAD_GLOBAL 2 (int)
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16 LOAD_GLOBAL 3 (N)
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18 LOAD_GLOBAL 4 (M)
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20 BINARY_MULTIPLY
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22 CALL_FUNCTION 1
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24 LOAD_GLOBAL 4 (M)
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26 CALL_FUNCTION 3
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28 GET_ITER
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>> 30 FOR_ITER 24 (to 80)
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32 STORE_FAST 2 (i)
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14 34 LOAD_GLOBAL 1 (range)
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36 LOAD_CONST 1 (0)
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38 LOAD_GLOBAL 5 (len)
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40 LOAD_FAST 0 (ls)
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42 CALL_FUNCTION 1
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44 CALL_FUNCTION 2
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46 GET_ITER
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>> 48 FOR_ITER 14 (to 78)
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50 STORE_FAST 3 (j)
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15 52 LOAD_FAST 0 (ls)
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54 LOAD_FAST 3 (j)
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56 BINARY_SUBSCR
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58 LOAD_FAST 2 (i)
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60 COMPARE_OP 2 (==)
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62 POP_JUMP_IF_FALSE 38 (to 76)
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16 64 LOAD_FAST 1 (ct)
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66 LOAD_CONST 2 (1)
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68 INPLACE_ADD
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70 STORE_FAST 1 (ct)
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17 72 POP_TOP
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74 JUMP_FORWARD 1 (to 78)
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15 >> 76 JUMP_ABSOLUTE 24 (to 48)
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>> 78 JUMP_ABSOLUTE 15 (to 30)
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13 >> 80 LOAD_CONST 0 (None)
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82 RETURN_VALUE
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```
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Whereas the `in` variant only compiles to 54.
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```python
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import dis
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def operatorSearch():
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ls = generateInputs()
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ct = 0
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for i in range(0, int(N*M), M):
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if i in ls:
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ct += 1
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dis.dis(operatorSearch)
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```
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```output
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4 0 LOAD_GLOBAL 0 (generateInputs)
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2 CALL_FUNCTION 0
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4 STORE_FAST 0 (ls)
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5 6 LOAD_CONST 1 (0)
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8 STORE_FAST 1 (ct)
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6 10 LOAD_GLOBAL 1 (range)
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12 LOAD_CONST 1 (0)
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14 LOAD_GLOBAL 2 (int)
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16 LOAD_GLOBAL 3 (N)
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18 LOAD_GLOBAL 4 (M)
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20 BINARY_MULTIPLY
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22 CALL_FUNCTION 1
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24 LOAD_GLOBAL 4 (M)
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26 CALL_FUNCTION 3
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28 GET_ITER
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>> 30 FOR_ITER 10 (to 52)
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32 STORE_FAST 2 (i)
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7 34 LOAD_FAST 2 (i)
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36 LOAD_FAST 0 (ls)
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38 CONTAINS_OP 0
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40 POP_JUMP_IF_FALSE 25 (to 50)
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8 42 LOAD_FAST 1 (ct)
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44 LOAD_CONST 2 (1)
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46 INPLACE_ADD
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48 STORE_FAST 1 (ct)
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>> 50 JUMP_ABSOLUTE 15 (to 30)
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6 >> 52 LOAD_CONST 0 (None)
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54 RETURN_VALUE
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```
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##
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