Which method executed first in Python?
When you are working with functions it is really important to know the order in which statements are executed. This is called the flow of execution and we’ve already talked about it a number of times in this chapter. Execution always begins at the first statement of the program. Statements are executed one at a time, in order, from top to bottom. Function definitions do
not alter the flow of execution of the program, but remember that statements inside the function are not executed until the function is called. Function calls are like a detour in the flow of execution. Instead of going to the next statement, the flow jumps to the first line of the called function, executes all the statements there, and then comes back to pick up where it left off. That sounds simple enough, until you remember that one function can call another. While in the middle of one
function, the program might have to execute the statements in another function. But while executing that new function, the program might have to execute yet another function! Fortunately, Python is adept at keeping track of where it is, so each time a function completes, the program picks up where it left off in the function that called it. When it gets to the end of the program, it terminates. What’s the moral of this sordid tale? When you read a program, don’t read from top to
bottom. Instead, follow the flow of execution. This means that you will read the Check your understanding Consider the following Python code. Note that line numbers are included on the left. 1def pow(b, p): 2 y = b ** p 3 return y 4 5def square(x): 6 a = pow(x, 2) 7 return a 8 9n = 5 10result = square(n) 11print(result) Which of the following best reflects the order in which these lines of code are processed in Python? Consider the following Python code. Note that line numbers are included on the left. 1def pow(b, p): 2 y = b ** p 3 return y 4 5def square(x): 6 a = pow(x, 2) 7 return a 8 9n = 5 10result = square(n) 11print(result) What does this function print? You have attempted of activities on this page What executes first in Python?Python Main Function is the beginning of any Python program. When we run a program, the interpreter runs the code sequentially and will not run the main function if imported as a module, but the Main Function gets executed only when it is run as a Python program.
What is the order of execution in Python?Execution always begins at the first statement of the program. Statements are executed one at a time, in order from top to bottom. Function definitions do not alter the flow of execution of the program, but remember that statements inside the function are not executed until the function is called.
How the execution starts in Python?The execution of the code starts from the starting line and goes line by line. It does not matter where the main function is present or it is present or not.
What is the first argument of a method Python?The first argument of every class method, including init , is always a reference to the current instance of the class. By convention, this argument is always named self. In the init method, self refers to the newly created object; in other class methods, it refers to the instance whose method was called.
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