perf(python): Much faster Series construction from subclasses of standard Python types

[alexander-beedie]

Took another look at Series construction following #20157, and found some additional large speedups (though in a more niche context).

Data composed of types that inherit from the standard builtin types (int, float, str, bytes) currently use the generic new_object constructor; however, it is actually still valid to use the specialised/fast-path constructors in this case. This PR makes a minor update to py_type_to_constructor to detect the inheritance chain and assign the faster constructors.

Example

import polars as pl
import codecs

class BinaryReprInt(int):
    def __new__(cls, value):
        return super().__new__(cls, value)

    def __repr__(self) -> str:
        v = f"{abs(int(self)):>08b}"
        return f"-{v}" if self < 0 else v

    __str__ = __repr__


bn = BinaryReprInt(12345)
print(bn)
# 11000000111001

bn == 12345
# True

int_data = list(range(10_000_000))
custom_int_data = [BinaryReprInt(i) for i in int_data]

with Timer():
    s = pl.Series(custom_int_data)

Timings

Before: 0.2938 secs
 After: 0.0805 secs  (~3½ times faster)  🚀 

Type comparison

Applying this update shows a different degree of speedup for different base types, but all speedups are significant; the table below shows timings when loading 10,000,000 elements that inherit from the given type:

dtype	before (secs)	after (secs)	speedup
bytes	0.9838	0.1071	9.2x
float	0.2554	0.0533	4.8x
int	0.3010	0.0816	3.7x
str	0.5904	0.3167	1.9x

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.63%. Comparing base (cbc0ea0) to head (434301e).
Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #20166      +/-   ##
==========================================
+ Coverage   79.58%   79.63%   +0.05%     
==========================================
  Files        1564     1564              
  Lines      217475   217448      -27     
  Branches     2472     2473       +1     
==========================================
+ Hits       173070   173162      +92     
+ Misses      43837    43717     -120     
- Partials      568      569       +1     

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[ritchie46]

I see you learned some Dutch.