What are the data types that python does not support?

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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