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The most commonly used methods of constructing a multi-word variable name are the last three examples: As with many things, it is a matter of personal preference, but most people would find the first two examples, where the letters are all shoved together, to be harder to read, particularly the one in all capital letters. On the other hand, they aren’t all necessarily equally legible. At least you can tell from the name what the value of the variable is supposed to represent. number_of_college_graduates ) 2500 2500 2500 2500 2500Īll of them are probably better choices than n, or ncg, or the like. numberOfCollegeGraduates, NumberOfCollegeGraduates. > numberofcollegegraduates = 2500 > NUMBEROFCOLLEGEGRADUATES = 2500 > numberOfCollegeGraduates = 2500 > NumberOfCollegeGraduates = 2500 > number_of_college_graduates = 2500 > print ( numberofcollegegraduates, NUMBEROFCOLLEGEGRADUATES. An additional restriction is that, although a variable name can contain digits, the first character of a variable name cannot be a digit. Officially, variable names in Python can be any length and can consist of uppercase and lowercase letters ( A-Z, a-z), digits ( 0-9), and the underscore character ( _).
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In fact, it is usually beneficial if they are because it makes the purpose of the variable more evident at first glance. The examples you have seen so far have used short, terse variable names like m and n.
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Thus, when you assign separate variables to an integer value in this range, they will actually reference the same object. But in this case, id(m) and id(n) are identical!įor purposes of optimization, the interpreter creates objects for the integers in the range at startup, and then reuses them during program execution. Here, m and n are separately assigned to integer objects having value 30.
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