"""Group words by length while preserving their relative order."""def group_by_length(words: list[str]) -> dict[int, list[str]]:    """Group words by their length, preserving their relative order.    words: list[str] - the list of words to group by length    returns: a dictionary mapping each word length to the list of words of        that length in their original order    """    result: dict[int, list[str]] = {}    word_item: str    for word_item in words:        length: int = len(word_item)        bucket: list[str] = result.setdefault(length, [])        bucket.append(word_item)    return result"""Module to calculate the next weekday following a given date."""from datetime import date, timedeltaSATURDAY_WEEKDAY: int = 5def next_weekday(day: date) -> date:    """Return the earliest weekday that is strictly after the given date.    day: date - the starting date    returns: the earliest weekday that is strictly after the given date    """    candidate: date = day + timedelta(days=1)    while candidate.weekday() >= SATURDAY_WEEKDAY:        candidate = candidate + timedelta(days=1)    return candidate"""Module for calculating the total size of Python files in a directory."""from pathlib import Pathdef total_python_bytes(directory: Path) -> int:    """Calculate the total size in bytes of all .py files recursively."""    if not directory.exists():        message = f"Directory does not exist: {directory}"        raise FileNotFoundError(message)    total_size: int = 0    item: Path    for item in directory.rglob("*.py"):        total_size += item.stat().st_size    return total_size"""Module providing the unique_in_order function for removing consecutive duplicates."""def unique_in_order(values: list[int]) -> list[int]:    """Remove consecutive duplicate elements from a list of integers."""    result: list[int] = []    has_previous: bool = False    previous: int = 0    for current in values:        if not has_previous:            result.append(current)            previous = current            has_previous = True        elif current != previous:            result.append(current)            previous = current    return result"""Module for computing vector dot products."""def dot_product(first: list[int], second: list[int]) -> int:    """Compute the dot product of two integer vectors.    Raises ValueError if their lengths differ.    """    if len(first) != len(second):        message = "Vectors must have the same length"        raise ValueError(message)    total: int = 0    index: int = 0    while index < len(first):        total += first[index] * second[index]        index += 1    return total"""Module to calculate the weekday name from an ISO 8601 date string."""from datetime import datedef weekday_name(date_text: str) -> str:    """Parse an ISO 8601 date string and return the English name of its weekday.    date_text: str - An ISO 8601 date string (e.g., 'YYYY-MM-DD')    returns: The full English name of the weekday (e.g. 'Monday')    """    try:        parsed_date: date = date.fromisoformat(date_text)    except ValueError as err:        message = "invalid ISO 8601 date string"        raise ValueError(message) from err    return parsed_date.strftime("%A")"""Environment integer lookup module."""from collections.abc import Mappingdef env_int(environment: Mapping[str, str], name: str, default: int) -> int:    """Read an integer from an environment mapping.    Returns the default if absent or raises ValueError if invalid.    """    if name not in environment:        return default    raw_value: str = environment[name]    try:        return int(raw_value)    except ValueError as error:        message = "Environment variable is not a valid integer."        raise ValueError(message) from error"""Module to read UTF-8 lines from a text file."""from pathlib import Pathdef read_utf8_lines(path: Path) -> list[str]:    """Read a UTF-8 text file and return its lines without their line endings."""    text = path.read_text(encoding="utf-8")    if not text:        return []    if text.endswith(("\r\n",)):        lines = text[:-2].splitlines()        lines.append("")        return lines    if text.endswith(("\n", "\r")):        lines = text[:-1].splitlines()        lines.append("")        return lines    return text.splitlines()

"""Group words by length while preserving their relative order."""def group_by_length(words: list[str]) -> dict[int, list[str]]:    """Group words by their length, preserving their relative order.    words: list[str] - the list of words to group by length    returns: a dictionary mapping each word length to the list of words of        that length in their original order    """    result: dict[int, list[str]] = {}    word_item: str    for word_item in words:        length: int = len(word_item)        bucket: list[str] = result.setdefault(length, [])        bucket.append(word_item)    return result"""Module to calculate the next weekday following a given date."""from datetime import date, timedeltaSATURDAY_WEEKDAY: int = 5def next_weekday(day: date) -> date:    """Return the earliest weekday that is strictly after the given date.    day: date - the starting date    returns: the earliest weekday that is strictly after the given date    """    candidate: date = day + timedelta(days=1)    while candidate.weekday() >= SATURDAY_WEEKDAY:        candidate = candidate + timedelta(days=1)    return candidate"""Module for calculating the total size of Python files in a directory."""from pathlib import Pathdef total_python_bytes(directory: Path) -> int:    """Calculate the total size in bytes of all .py files recursively."""    if not directory.exists():        message = f"Directory does not exist: {directory}"        raise FileNotFoundError(message)    total_size: int = 0    item: Path    for item in directory.rglob("*.py"):        total_size += item.stat().st_size    return total_size"""Module providing the unique_in_order function for removing consecutive duplicates."""def unique_in_order(values: list[int]) -> list[int]:    """Remove consecutive duplicate elements from a list of integers."""    result: list[int] = []    has_previous: bool = False    previous: int = 0    for current in values:        if not has_previous:            result.append(current)            previous = current            has_previous = True        elif current != previous:            result.append(current)            previous = current    return result"""Module for computing vector dot products."""def dot_product(first: list[int], second: list[int]) -> int:    """Compute the dot product of two integer vectors.    Raises ValueError if their lengths differ.    """    if len(first) != len(second):        message = "Vectors must have the same length"        raise ValueError(message)    total: int = 0    index: int = 0    while index < len(first):        total += first[index] * second[index]        index += 1    return total"""Module to calculate the weekday name from an ISO 8601 date string."""from datetime import datedef weekday_name(date_text: str) -> str:    """Parse an ISO 8601 date string and return the English name of its weekday.    date_text: str - An ISO 8601 date string (e.g., 'YYYY-MM-DD')    returns: The full English name of the weekday (e.g. 'Monday')    """    try:        parsed_date: date = date.fromisoformat(date_text)    except ValueError as err:        message = "invalid ISO 8601 date string"        raise ValueError(message) from err    return parsed_date.strftime("%A")"""Environment integer lookup module."""from collections.abc import Mappingdef env_int(environment: Mapping[str, str], name: str, default: int) -> int:    """Read an integer from an environment mapping.    Returns the default if absent or raises ValueError if invalid.    """    if name not in environment:        return default    raw_value: str = environment[name]    try:        return int(raw_value)    except ValueError as error:        message = "Environment variable is not a valid integer."        raise ValueError(message) from error"""Module to read UTF-8 lines from a text file."""from pathlib import Pathdef read_utf8_lines(path: Path) -> list[str]:    """Read a UTF-8 text file and return its lines without their line endings."""    text = path.read_text(encoding="utf-8")    if not text:        return []    if text.endswith(("\r\n",)):        lines = text[:-2].splitlines()        lines.append("")        return lines    if text.endswith(("\n", "\r")):        lines = text[:-1].splitlines()        lines.append("")        return lines    return text.splitlines()

"""Module to count lines matching a substring in a text file."""from pathlib import pathlib_module  # Not used directly, kept simple via Path importfrom pathlib import Pathdef count_lines_matching(path: Path, text: str) -> int:    """Count how many lines in a text file contain a given substring."""    resolved_path: Path = path.resolve()    if not resolved_path.is_file():        message = "File does not exist"        raise FileNotFoundError(message)    content: str = resolved_path.read_text(encoding="utf-8")    lines: list[str] = content.splitlines(keepends=False)    if not lines:        if content == "":            return 0    count: int = 0    line: str    for line in lines:        if text in line:            count += 1    return count"""Module for computing the SHA-256 hex digest of a file by reading it in chunks."""from hashlib import sha256from pathlib import Pathdef file_sha256(path: Path) -> str:    """Compute the SHA-256 hex digest of a file by reading it in chunks."""    hasher = sha256()    buffer_size: int = 65536    with path.open("rb") as file_handle:        while True:            chunk: bytes = file_handle.read(buffer_size)            if not chunk:                break            hasher.update(chunk)    return hasher.hexdigest()"""Module providing URL slugification utilities."""def slugify(text: str) -> str:    """Convert a string to a URL-friendly slug.    Lowercases the text, drops everything except letters, digits, and spaces,    and joins the resulting words with single dashes.    """    lowered = text.lower()    allowed_chars = [char for char in lowered if char.isalnum() or char.isspace()]    filtered = "".join(allowed_chars)    parts = filtered.split()    return "-".join(parts)"""Binary search implementation over a sorted list of integers."""from __dl_placeholder import *  # type: ignoredef binary_search(values: list[int], wanted: int) -> int:    """Find the index of a value in a sorted list of integers using binary search.    Returns the index of wanted if present, otherwise -1.    """    left: int = 0    right: int = len(values) - 1    while left <= right:        mid: int = left + (right - left) // 2        current: int = values[mid]        if current == wanted:            return mid        if current < wanted:            left = mid + 1        else:            right = mid - 1    return -1"""Calculate the absolute number of days between two ISO 8601 date strings."""from datetime import datedef days_between(first: str, second: str) -> int:    """Return the absolute number of days between two ISO 8601 date strings.    Parses both string arguments into date objects and computes the absolute    difference in days. Raises ValueError if either string is invalid.    """    first_date: date = date.fromisoformat(first)    second_date: date = date.fromisoformat(second)    difference: int = abs((second_date - first_date).days)    return difference"""Module for counting whitespace-separated words in a text file."""from pathlib import Pathdef count_words(path: Path) -> int:    """Count the number of whitespace-separated words in a text file.    path: Path - path to the text file to read    returns: the total count of whitespace-separated words in the file    """    text: str = path.read_text(encoding="utf-8")    words: list[str] = text.split()    return len(words)

"""Module to count lines matching a substring in a text file."""from pathlib import pathlib_module  # Not used directly, kept simple via Path importfrom pathlib import Pathdef count_lines_matching(path: Path, text: str) -> int:    """Count how many lines in a text file contain a given substring."""    resolved_path: Path = path.resolve()    if not resolved_path.is_file():        message = "File does not exist"        raise FileNotFoundError(message)    content: str = resolved_path.read_text(encoding="utf-8")    lines: list[str] = content.splitlines(keepends=False)    if not lines:        if content == "":            return 0    count: int = 0    line: str    for line in lines:        if text in line:            count += 1    return count"""Module for computing the SHA-256 hex digest of a file by reading it in chunks."""from hashlib import sha256from pathlib import Pathdef file_sha256(path: Path) -> str:    """Compute the SHA-256 hex digest of a file by reading it in chunks."""    hasher = sha256()    buffer_size: int = 65536    with path.open("rb") as file_handle:        while True:            chunk: bytes = file_handle.read(buffer_size)            if not chunk:                break            hasher.update(chunk)    return hasher.hexdigest()"""Module providing URL slugification utilities."""def slugify(text: str) -> str:    """Convert a string to a URL-friendly slug.    Lowercases the text, drops everything except letters, digits, and spaces,    and joins the resulting words with single dashes.    """    lowered = text.lower()    allowed_chars = [char for char in lowered if char.isalnum() or char.isspace()]    filtered = "".join(allowed_chars)    parts = filtered.split()    return "-".join(parts)"""Binary search implementation over a sorted list of integers."""from __dl_placeholder import *  # type: ignoredef binary_search(values: list[int], wanted: int) -> int:    """Find the index of a value in a sorted list of integers using binary search.    Returns the index of wanted if present, otherwise -1.    """    left: int = 0    right: int = len(values) - 1    while left <= right:        mid: int = left + (right - left) // 2        current: int = values[mid]        if current == wanted:            return mid        if current < wanted:            left = mid + 1        else:            right = mid - 1    return -1"""Calculate the absolute number of days between two ISO 8601 date strings."""from datetime import datedef days_between(first: str, second: str) -> int:    """Return the absolute number of days between two ISO 8601 date strings.    Parses both string arguments into date objects and computes the absolute    difference in days. Raises ValueError if either string is invalid.    """    first_date: date = date.fromisoformat(first)    second_date: date = date.fromisoformat(second)    difference: int = abs((second_date - first_date).days)    return difference"""Module for counting whitespace-separated words in a text file."""from pathlib import Pathdef count_words(path: Path) -> int:    """Count the number of whitespace-separated words in a text file.    path: Path - path to the text file to read    returns: the total count of whitespace-separated words in the file    """    text: str = path.read_text(encoding="utf-8")    words: list[str] = text.split()    return len(words)

"""Module to count lines matching a substring in a text file."""from pathlib import pathlib_module  # Not used directly, kept simple via Path importfrom pathlib import Pathdef count_lines_matching(path: Path, text: str) -> int:    """Count how many lines in a text file contain a given substring."""    resolved_path: Path = path.resolve()    if not resolved_path.is_file():        message = "File does not exist"        raise FileNotFoundError(message)    content: str = resolved_path.read_text(encoding="utf-8")    lines: list[str] = content.splitlines(keepends=False)    if not lines:        if content == "":            return 0    count: int = 0    line: str    for line in lines:        if text in line:            count += 1    return count"""Module for computing the SHA-256 hex digest of a file by reading it in chunks."""from hashlib import sha256from pathlib import Pathdef file_sha256(path: Path) -> str:    """Compute the SHA-256 hex digest of a file by reading it in chunks."""    hasher = sha256()    buffer_size: int = 65536    with path.open("rb") as file_handle:        while True:            chunk: bytes = file_handle.read(buffer_size)            if not chunk:                break            hasher.update(chunk)    return hasher.hexdigest()"""Module providing URL slugification utilities."""def slugify(text: str) -> str:    """Convert a string to a URL-friendly slug.    Lowercases the text, drops everything except letters, digits, and spaces,    and joins the resulting words with single dashes.    """    lowered = text.lower()    allowed_chars = [char for char in lowered if char.isalnum() or char.isspace()]    filtered = "".join(allowed_chars)    parts = filtered.split()    return "-".join(parts)"""Binary search implementation over a sorted list of integers."""from __dl_placeholder import *  # type: ignoredef binary_search(values: list[int], wanted: int) -> int:    """Find the index of a value in a sorted list of integers using binary search.    Returns the index of wanted if present, otherwise -1.    """    left: int = 0    right: int = len(values) - 1    while left <= right:        mid: int = left + (right - left) // 2        current: int = values[mid]        if current == wanted:            return mid        if current < wanted:            left = mid + 1        else:            right = mid - 1    return -1"""Calculate the absolute number of days between two ISO 8601 date strings."""from datetime import datedef days_between(first: str, second: str) -> int:    """Return the absolute number of days between two ISO 8601 date strings.    Parses both string arguments into date objects and computes the absolute    difference in days. Raises ValueError if either string is invalid.    """    first_date: date = date.fromisoformat(first)    second_date: date = date.fromisoformat(second)    difference: int = abs((second_date - first_date).days)    return difference"""Module for counting whitespace-separated words in a text file."""from pathlib import Pathdef count_words(path: Path) -> int:    """Count the number of whitespace-separated words in a text file.    path: Path - path to the text file to read    returns: the total count of whitespace-separated words in the file    """    text: str = path.read_text(encoding="utf-8")    words: list[str] = text.split()    return len(words)

"""Module to count lines matching a substring in a text file."""from pathlib import pathlib_module  # Not used directly, kept simple via Path importfrom pathlib import Pathdef count_lines_matching(path: Path, text: str) -> int:    """Count how many lines in a text file contain a given substring."""    resolved_path: Path = path.resolve()    if not resolved_path.is_file():        message = "File does not exist"        raise FileNotFoundError(message)    content: str = resolved_path.read_text(encoding="utf-8")    lines: list[str] = content.splitlines(keepends=False)    if not lines:        if content == "":            return 0    count: int = 0    line: str    for line in lines:        if text in line:            count += 1    return count"""Module for computing the SHA-256 hex digest of a file by reading it in chunks."""from hashlib import sha256from pathlib import Pathdef file_sha256(path: Path) -> str:    """Compute the SHA-256 hex digest of a file by reading it in chunks."""    hasher = sha256()    buffer_size: int = 65536    with path.open("rb") as file_handle:        while True:            chunk: bytes = file_handle.read(buffer_size)            if not chunk:                break            hasher.update(chunk)    return hasher.hexdigest()"""Module providing URL slugification utilities."""def slugify(text: str) -> str:    """Convert a string to a URL-friendly slug.    Lowercases the text, drops everything except letters, digits, and spaces,    and joins the resulting words with single dashes.    """    lowered = text.lower()    allowed_chars = [char for char in lowered if char.isalnum() or char.isspace()]    filtered = "".join(allowed_chars)    parts = filtered.split()    return "-".join(parts)"""Binary search implementation over a sorted list of integers."""from __dl_placeholder import *  # type: ignoredef binary_search(values: list[int], wanted: int) -> int:    """Find the index of a value in a sorted list of integers using binary search.    Returns the index of wanted if present, otherwise -1.    """    left: int = 0    right: int = len(values) - 1    while left <= right:        mid: int = left + (right - left) // 2        current: int = values[mid]        if current == wanted:            return mid        if current < wanted:            left = mid + 1        else:            right = mid - 1    return -1"""Calculate the absolute number of days between two ISO 8601 date strings."""from datetime import datedef days_between(first: str, second: str) -> int:    """Return the absolute number of days between two ISO 8601 date strings.    Parses both string arguments into date objects and computes the absolute    difference in days. Raises ValueError if either string is invalid.    """    first_date: date = date.fromisoformat(first)    second_date: date = date.fromisoformat(second)    difference: int = abs((second_date - first_date).days)    return difference"""Module for counting whitespace-separated words in a text file."""from pathlib import Pathdef count_words(path: Path) -> int:    """Count the number of whitespace-separated words in a text file.    path: Path - path to the text file to read    returns: the total count of whitespace-separated words in the file    """    text: str = path.read_text(encoding="utf-8")    words: list[str] = text.split()    return len(words)

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A model was asked for one small function. Its first try imported a name that doesn't exist. Pinull refused it, sent it back with the reason, and handed over the next try only once every check held.

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refuted module 'pathlib' has no attribute or submodule 'pathlib_module' — Pinull

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A real run, replayed · gemini-3.5-flash-lite · CPython 3.13

Proof

Measured,
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323 invented names, planted in real Python code. Not one was passed as real.

0passed as real

267 refuted, with the reason
54 flagged as unproven
2 safely guarded in the code

Each square is one invented name.

0.158

false alarms per 1,000 references in Python's standard library

858

automated tests, each tied to a promise

Real bugs it found in software everyone uses.

Filed by us. Confirmed by their maintainers.

CPythonIDLE: ScrolledCanvas.zoom_height calls idlelib.zoomheight.zoom_height, which has not existed since 2019OpenConfirmed by the IDLE maintainer; on hold while the code it lives in is replaced.python/cpython#157762 ↗CPythonctypes.util.test() calls cdll.load, which LibraryLoader does not haveClosed as completedClosed as completed by CPython core developers.python/cpython#157763 ↗Pydanticpydantic.v1._hypothesis_plugin cannot be imported under pydantic 2Closed — not fixedReproduced by a contributor and confirmed by a maintainer; left as it is, since the module is unused.pydantic/pydantic#13835 ↗

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