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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

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AI & LLM integration patterns easy

How to Build a Zero-Shot Classification Prompt in Python

Creates a prompt for zero-shot text classification by pairing input text with candidate labels and a hypothesis template.

zero-shot prompt classification
Python
from typing import Dict, List


def build_zero_shot_prompt(
    text: str,
    candidate_labels: List[str],
    hypothesis_template: str = "This is about {}.",
) -> Dict[str, List[str]]:
    """Build a prompt ready for zero-shot classification."""
    return {
        "sequences": text,
        "candidate_labels": can…
13 0 Open
Testing & modern typing easy

How to Test Hypotheses with Property-Based Check in Python

A Python search that checks an integer property (palindrome divisible by digit sum) and returns the first counterexample within a range, with exactly reproduced output from the code.

hypothesis testing palindrome
Python
def is_property_satisfied(n):
    """
    Demonstrates a mathematically inspired property:
    checks whether n is both a palindrome and divisible by its digit sum.
    """
    s = str(n)
    if s != s[::-1]:
        return False
    digit_sum = sum(int(d) for d in s)
    return digit_sum != 0 and n % digit_sum == 0

…
10 0 Open
Testing & modern typing medium

How to Use Hypothesis Strategies for Lists of Text in Python

Generate random lists of non-empty strings with Hypothesis and verify that joining them with a comma-and-space separator meets expected length and containment invariants.

hypothesis property-based-testing strategies
Python
from hypothesis import given, strategies as st
from hypothesis import example


@given(st.lists(st.text(min_size=1, max_size=10), min_size=1, max_size=5))
def test_joined_string_length(items):
    """Each text is non-empty; a joined string should be at least as long
    as the number of items (separator adds character…
13 0 Open
A/B testing & experimentation medium

Benjamini Hochberg FDR Correction in Python

Implement the Benjamini-HHochberg false discovery rate (FDR) procedure in Python to control the expected proportion of false positives among rejected hypotheses.

fdr multiple testing hypothesis testing
Python
import numpy as np

def benjamini_hochberg(p_values, alpha=0.05):
    p_values = np.array(p_values)
    n = len(p_values)
    sorted_idx = np.argsort(p_values)
    sorted_p = p_values[sorted_idx]
    
    thresholds = (np.arange(1, n + 1) / n) * alpha
    significant = sorted_p <= thresholds
    
    if not significan…
14 0 Open
A/B testing & experimentation medium

Chi-Square Test in Python for Conversion Mock Data

Compute the chi-square statistic and approximate p-value for a mock A/B conversion test using the standard library.

chi-square statistics ab-testing
Python
import math
from collections import Counter

def chi_square_statistic(observed):
    """
    Compute chi-square statistic for a mock conversion test.
    observed: dict mapping outcomes to observed frequencies.
    """
    observed = Counter(observed)
    n = sum(observed.values())
    expected = n / len(observed) if …
12 0 Open
A/B testing & experimentation medium

How to Compute Mann-Whitney U Test in Python

Compute the Mann-Whitney U statistic and p-value manually in Python with tie correction and a normal approximation for independent samples.

statistics hypothesis-testing ab-testing
Python
import numpy as np
from scipy import stats

def mann_whitney_u_mock(sample_a, sample_b):
    """Compute Mann-Whitney U and p-value manually."""
    # Combine and rank
    combined = sample_a + sample_b
    n_a, n_b = len(sample_a), len(sample_b)
    n_total = n_a + n_b
    
    # Rank with ties handling (average ranks…
12 0 Open
A/B testing & experimentation medium

How to Conduct a Two-Sample T-Test in Python

Performs Welch's t-test for two independent samples, computing the t-statistic, degrees of freedom, and p-value using NumPy and SciPy.

statistics hypothesis-testing t-test
Python
import numpy as np

def two_sample_t_test(sample1, sample2):
    """Perform Welch's t-test for two independent samples."""
    n1, n2 = len(sample1), len(sample2)
    mean1, mean2 = np.mean(sample1), np.mean(sample2)
    var1, var2 = np.var(sample1, ddof=1), np.var(sample2, ddof=1)

    # Standard error of difference
…
15 0 Open
A/B testing & experimentation medium

How to Perform Welch's t-Test in Python

Calculate the Welch t-statistic and degrees of freedom for two samples with unequal variances using Python's statistics module.

statistics t-test hypothesis-testing
Python
import math
from statistics import mean, variance


def welch_t_test(sample1, sample2):
    n1, n2 = len(sample1), len(sample2)
    mean1, mean2 = mean(sample1), mean(sample2)
    var1, var2 = variance(sample1), variance(sample2)

    # Welch's t statistic
    t_stat = (mean1 - mean2) / math.sqrt(var1 / n1 + var2 / n2…
14 0 Open
A/B testing & experimentation medium

How to Run a Permutation Test in Python

Run a Monte Carlo permutation test to compute a p-value for comparing two group means without parametric assumptions.

permutation-test statistics ab-testing
Python
import random
import statistics

def permutation_test(group_a, group_b, n_permutations=10000, seed=42):
    random.seed(seed)
    combined = group_a + group_b
    observed_diff = abs(statistics.mean(group_a) - statistics.mean(group_b))
    
    count = 0
    n = len(group_a)
    for _ in range(n_permutations):
       …
15 0 Open

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Copy-ready Python snippets for learners and developers

PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.

How to use this library

  1. Pick a topic section — strings, lists, files, functions, and more
  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

Samples vs tutorials and challenges

Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.