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Python does not have char or byte types to store single characters or 8-bit integers. You can use strings of length 1 to represent characters or 8-bit integers.
In Python, the space occupied by each character in the string is bit. (Recommended learning: Python video tutorial)
>>> import sys >>> sys.getsizeof('') 37 >>> sys.getsizeof('a') 38
It can be seen that the null character occupies 37 bytes, and the string 'a' with a length of 1 occupies 38 bytes of memory. After one more character a, there is one more byte.
Internally in Python, string is implemented like this
typedef struct { PyObject_VAR_HEAD long ob_shash; int ob_sstate; char ob_sval[1]; /* Invariants: * ob_sval contains space for 'ob_size+1' elements. * ob_sval[ob_size] == 0. * ob_shash is the hash of the string or -1 if not computed yet. * ob_sstate != 0 iff the string object is in stringobject.c's * 'interned' dictionary; in this case the two references * from 'interned' to this object are *not counted* in ob_refcnt. */ } PyStringObject;
Each char is stored in ob_sval, accounting for 8 bits in size. The remaining 36 bytes mainly come from the macro PyObject_VAR_HEAD. In fact, python's string implementation also uses a global variable called *interned, which can Storing strings of length 0 or 1, that is, char, can save space and speed up.
In fact, there are neither pointers nor "naked data structures" (non-objects) in python, even most Simple integers are implemented in this way
typedef struct { PyObject_HEAD long ob_ival; } PyIntObject;
In short, this design satisfies Python's design philosophy of "everything is an object♂" and "everything is as simple as possible".
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