Files
fn_registry/python/functions/datascience/automatic_eda/chapters/modelos.py
T
egutierrez a421f13d2e feat(eda): engancha glosario clicable en correlacion/modelos/agregacion
Fase 4b — extiende el glosario clicable de AutomaticEDA (mecanismo ya probado
end-to-end con `entropia` en cat_distr) a tres capítulos más, siguiendo el
contrato sección 11 (glossary.add(key,label,def) + span [[term:KEY]]texto[[/term]]):

- correlacion: Pearson, Spearman, Cramér's V, razón de correlación (η) y la
  corrección por comparaciones múltiples (FDR). Los métodos se marcan en el
  intro (siempre presente); FDR se registra y marca solo cuando se emite su
  resumen, para no dejar entradas de glosario sin aparición que las referencie.
- modelos: PCA, KMeans, coeficiente de silueta (silhouette), Isolation Forest y
  la estandarización z-score. Cada término se registra dentro de la sección que
  lo usa (tras su early-return), de modo que un término solo entra al glosario
  cuando su sección realmente se renderiza.
- agregacion: agrupación (split-apply-combine / groupby) y tabla dinámica
  (pivot), ambos en el intro siempre presente.

Solo se añaden los enganches de glosario: ningún cambio en la lógica de datos.
El texto visible es idéntico con o sin marcador (los renderers lo eliminan),
así que el layout de línea no cambia. Sin colector en ctx (render suelto) los
capítulos degradan y no marcan nada.

Tests: un test de glosario por capítulo verifica registro + marcado y la
degradación sin colector. Suite AutomaticEDA + render pipeline: 87 passed.
Golden titanic (run_models+series+llm): los 12 términos aparecen como entradas
del glosario en PDF (16 link annotations GOTO) y PPTX (15 saltos hlinksldjump).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-30 18:02:31 +02:00

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"""Models chapter (MODELOS) — cheap unsupervised models, rendered as markdown.
Builds the *Modelos* chapter of an AutomaticEDA document from the ``models``
block of a TableProfile (``run_eda_models`` output: ``{pca, kmeans, outliers,
normality}``). It renders, as structured markdown/tables/figures that the core
paginator never cuts:
1. **Normalization note** — every multivariate model below standardizes the
columns with z-score first; the chapter explains why (different scales would
otherwise dominate distance/variance).
2. **PCA** — a scree plot (explained + cumulative variance, single Y axis) plus
variance and top-loadings tables.
3. **KMeans segments** — a PCA scatter **coloured by cluster** (its own
page/slide), the cluster-size table, and a per-cluster LLM micro-analysis
with a title for each segment.
4. **Isolation Forest outliers** — a short explanation of how anomalous rows are
isolated multivariately and how the threshold is chosen, plus the counts.
5. **Normality** — per-column Jarque-Bera / D'Agostino / Shapiro verdicts.
The raw numeric data needed to colour the cluster scatter is **not** in the
TableProfile, so — exactly like ``overview`` reads ``head_rows`` from ``ctx`` —
this chapter looks for the cluster projection / raw numeric columns in ``ctx``
(or in ``profile``) and degrades honestly when they are absent: it falls back to
the uncoloured ``pca.projection`` with a note, or omits the scatter entirely.
ctx keys this chapter consumes (all optional):
cluster_projection : dict — a pre-computed ``project_clusters_2d`` result
(``points``/``labels``/``centers_2d``/``cluster_profiles``/...). Used
directly when present (forward-compatible with the calculation phase).
raw_numeric : dict — ``{col: [values]}`` raw numeric columns; when present
and ``cluster_projection`` is not, the chapter calls
``project_clusters_2d`` live to build points + aligned labels.
cluster_titles : list — pre-computed ``[{cluster, title, description}]``
(a ``describe_clusters_llm`` ``clusters`` list). Used for the per-cluster
micro-analysis without an LLM call (offline/tests).
run_cluster_llm : bool — when True and ``cluster_titles`` is absent, call
``describe_clusters_llm`` live on the cluster profiles.
cluster_llm_model : str — model id for the live LLM call.
Contract: build_<id>(profile, ctx) -> Chapter | None ; CHAPTER_VERSION = "x.y.z".
"""
from __future__ import annotations
from .. import model
CHAPTER_VERSION = "1.0.0"
CHAPTER_ID = "modelos"
CHAPTER_TITLE = "Modelos"
# Tableau-10 palette (matplotlib's default cycle) — used both for the matplotlib
# scatter and to keep the legend/colours stable per cluster index.
_CLUSTER_COLORS = [
"#4e79a7", "#f28e2b", "#e15759", "#76b7b2", "#59a14f",
"#edc948", "#b07aa1", "#ff9da7", "#9c755f", "#bab0ac",
]
# Glossary terms this chapter explains. Each is registered in the shared
# collector (ctx['glossary']) and marked clickable on its first appearance — the
# canonical two-step pattern (see ``cat_distr``): ``glossary.add(key, label,
# definition)`` + the inline span ``[[term:KEY]]texto[[/term]]`` in a Markdown
# block. A term is registered only when its section is actually rendered, so the
# glossary never lists an entry no in-text appearance points to.
_TERM_DEFS = {
"zscore": (
"Estandarización z-score",
"Transformación que lleva cada columna numérica a media 0 y desviación "
"típica 1: a cada valor le resta la media de su columna y lo divide por "
"la desviación típica. Así variables con escalas muy distintas (euros "
"frente a un ratio 01) pesan por igual en las distancias y la varianza."),
"pca": (
"PCA (componentes principales)",
"El análisis de componentes principales resume muchas variables "
"numéricas correlacionadas en pocos ejes nuevos (componentes), "
"ortogonales entre sí y ordenados por la cantidad de varianza que "
"capturan. Permite ver la estructura de los datos en 2D y saber cuántas "
"dimensiones bastan para explicarlos."),
"kmeans": (
"KMeans (segmentación)",
"Algoritmo de agrupamiento no supervisado que reparte las filas en k "
"segmentos: asigna cada fila al centro (centroide) más cercano y recoloca "
"los centroides de forma iterativa hasta minimizar la distancia interna "
"de cada grupo. Aquí k se elige automáticamente."),
"silhouette": (
"Coeficiente de silueta (silhouette)",
"Métrica de calidad de un agrupamiento, en el rango 1 a 1: para cada "
"fila compara cómo de cerca está de su propio segmento frente al segmento "
"vecino más próximo. Cuanto más alto el promedio, más compactos y "
"separados están los segmentos."),
"isolation_forest": (
"Isolation Forest (anomalías)",
"Algoritmo de detección de anomalías multivariante: construye árboles que "
"parten el espacio con cortes aleatorios y mide cuántos cortes hacen "
"falta para aislar cada fila. Las filas raras se aíslan con muy pocos "
"cortes y se marcan como outliers según un umbral de contaminación."),
}
def _term(mark: bool, key: str, text: str) -> str:
"""Wrap ``text`` as a clickable glossary span when ``mark`` is True.
The visible text is identical with or without the marker (the renderers strip
it), so wrapping never changes line layout — it only adds the link.
"""
return f"[[term:{key}]]{text}[[/term]]" if mark else text
def _register(gloss, key: str) -> None:
"""Register term ``key`` in the collector (idempotent); no-op if gloss None."""
if gloss is not None:
label, definition = _TERM_DEFS[key]
gloss.add(key, label, definition)
# --------------------------------------------------------------------------- #
# Formatting helpers (mirror the overview chapter's defensive style).
# --------------------------------------------------------------------------- #
def _fmt_num(value, decimals: int = 3) -> str:
if value is None:
return ""
if isinstance(value, bool):
return "" if value else "no"
if isinstance(value, int):
return f"{value:,}".replace(",", ".")
if isinstance(value, float):
if value != value: # NaN
return "NaN"
if value in (float("inf"), float("-inf")):
return str(value)
text = f"{value:.{decimals}f}".rstrip("0").rstrip(".")
return text if text else "0"
return model._safe_str(value)
def _fmt_pct_ratio(value, decimals: int = 1) -> str:
"""Format a 0..1 ratio as a percentage."""
if value is None:
return ""
try:
return f"{float(value) * 100:.{decimals}f}%"
except (TypeError, ValueError):
return model._safe_str(value)
def _fmt_pct_already(value, decimals: int = 2) -> str:
"""Format a value that is *already* a 0..100 percentage."""
if value is None:
return ""
try:
return f"{float(value):.{decimals}f}%"
except (TypeError, ValueError):
return model._safe_str(value)
def _is_dict(v) -> bool:
return isinstance(v, dict)
# --------------------------------------------------------------------------- #
# Cluster projection: prefer a pre-computed result, else compute it live, else
# fall back to the uncoloured PCA projection.
# --------------------------------------------------------------------------- #
def _resolve_cluster_projection(profile: dict, ctx: dict):
"""Return (projection_dict_or_None, source_label).
Order: ctx/profile['cluster_projection'] (pre-computed) → live
project_clusters_2d on ctx/profile['raw_numeric'] → None.
"""
pre = ctx.get("cluster_projection") or profile.get("cluster_projection")
models = profile.get("models") if _is_dict(profile.get("models")) else {}
if not pre and _is_dict(models):
pre = models.get("cluster_projection")
if _is_dict(pre) and pre.get("points"):
return pre, "precomputed"
raw = ctx.get("raw_numeric") or profile.get("raw_numeric")
if _is_dict(raw) and raw:
try:
# Import the submodule's function explicitly (avoid the package
# attribute shadowing the function with the same-named module).
from datascience.project_clusters_2d import project_clusters_2d
proj = project_clusters_2d(raw)
if _is_dict(proj) and proj.get("points"):
return proj, "live"
except Exception: # noqa: BLE001 — never break the chapter.
return None, "none"
return None, "none"
def _cluster_titles(profile: dict, ctx: dict, projection: dict):
"""Return a list of {cluster, title, description} for the segments.
Order: ctx['cluster_titles'] (pre-computed) → live describe_clusters_llm when
ctx['run_cluster_llm'] and we have cluster_profiles → derived titles from the
distinctive features → None.
"""
pre = ctx.get("cluster_titles")
if isinstance(pre, list) and pre:
return [c for c in pre if _is_dict(c)]
profiles = (projection or {}).get("cluster_profiles") or []
feats = (projection or {}).get("feature_names") or []
if ctx.get("run_cluster_llm") and profiles:
try:
from datascience.describe_clusters_llm import describe_clusters_llm
out = describe_clusters_llm(
profiles, feats,
model=ctx.get("cluster_llm_model", "claude-haiku-4-5-20251001"))
clusters = (out or {}).get("clusters")
if isinstance(clusters, list) and clusters:
return [c for c in clusters if _is_dict(c)]
except Exception: # noqa: BLE001
pass
# Derived fallback: name each cluster by its distinctive features.
if profiles:
derived = []
for p in profiles:
if not _is_dict(p):
continue
cid = p.get("cluster", len(derived))
dist = p.get("distinctive") or []
label = ", ".join(model._safe_str(d) for d in dist[:2]) if dist else ""
title = f"Segmento {cid}" + (f"{label}" if label else "")
derived.append({"cluster": cid, "title": title, "description": ""})
if derived:
return derived
return None
# --------------------------------------------------------------------------- #
# Figure builders (lazy: matplotlib only imported when the renderer draws them).
# --------------------------------------------------------------------------- #
def _make_scree(pca: dict):
"""Return a zero-arg callable drawing the PCA scree plot, or None."""
evr = pca.get("explained_variance_ratio") or []
cum = pca.get("cumulative") or []
if not evr:
return None
def _draw():
import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
comps = list(range(1, len(evr) + 1))
fig, ax = plt.subplots(figsize=(7.0, 4.2))
ax.bar(comps, evr, color="#4e79a7", alpha=0.85,
label="Varianza explicada")
if cum:
ax.plot(comps[:len(cum)], cum, color="#e15759", marker="o",
linewidth=1.8, label="Acumulada")
ax.set_xlabel("Componente principal")
ax.set_ylabel("Proporción de varianza")
ax.set_xticks(comps)
ax.set_ylim(0, 1.0)
ax.grid(axis="y", color="#dddddd", linewidth=0.6)
ax.legend(loc="best", fontsize=8, frameon=False)
ax.set_title("Varianza explicada por componente (PCA)", fontsize=10)
fig.tight_layout()
return fig
return _draw
def _make_cluster_scatter(projection: dict):
"""Return a zero-arg callable drawing the cluster scatter, or None."""
points = projection.get("points") or []
labels = projection.get("labels") or []
if not points or len(points) != len(labels):
return None
centers = projection.get("centers_2d") or []
explained = projection.get("explained_2d") or []
def _draw():
import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
fig, ax = plt.subplots(figsize=(7.0, 5.2))
uniq = sorted(set(int(l) for l in labels))
for cl in uniq:
xs = [p[0] for p, l in zip(points, labels) if int(l) == cl]
ys = [p[1] for p, l in zip(points, labels) if int(l) == cl]
color = _CLUSTER_COLORS[cl % len(_CLUSTER_COLORS)]
ax.scatter(xs, ys, s=14, c=color, alpha=0.7, linewidths=0,
label=f"Cluster {cl} (n={len(xs)})")
for cl, c in enumerate(centers):
color = _CLUSTER_COLORS[cl % len(_CLUSTER_COLORS)]
ax.scatter([c[0]], [c[1]], s=180, c=color, marker="X",
edgecolors="black", linewidths=1.2, zorder=5)
xlab, ylab = "PC1", "PC2"
if len(explained) >= 2:
xlab = f"PC1 ({_fmt_pct_ratio(explained[0])} var.)"
ylab = f"PC2 ({_fmt_pct_ratio(explained[1])} var.)"
ax.set_xlabel(xlab)
ax.set_ylabel(ylab)
ax.set_title("Segmentos KMeans proyectados sobre el plano PCA",
fontsize=10)
ax.grid(color="#eeeeee", linewidth=0.5)
ax.legend(loc="best", fontsize=8, frameon=True, framealpha=0.9)
fig.tight_layout()
return fig
return _draw
# --------------------------------------------------------------------------- #
# Section builders. Each returns a list of blocks (possibly empty).
# --------------------------------------------------------------------------- #
def _normalization_intro(gloss=None, mark_term: bool = False) -> list:
_register(gloss, "zscore")
zscore = _term(mark_term, "zscore", "**estandarizan con z-score**")
text = (
"Estos modelos son **no supervisados**: buscan estructura latente sin "
"una variable objetivo. Antes de aplicarlos, todas las columnas "
f"numéricas se {zscore} (cada valor menos la media, dividido por la "
"desviación típica). Sin esta normalización, una variable con escala "
"grande (p.ej. ingresos en euros) dominaría las distancias y la varianza "
"frente a otra de escala pequeña (p.ej. un ratio entre 0 y 1), sesgando "
"tanto el PCA como el KMeans. Tras la estandarización todas las variables "
"pesan por igual."
)
return [model.Heading(text="Modelos no supervisados", level=1),
model.Markdown(text=text)]
def _pca_section(pca: dict, gloss=None, mark_term: bool = False) -> list:
if not _is_dict(pca) or not pca.get("explained_variance_ratio"):
return []
_register(gloss, "pca")
blocks = [model.Heading(text="PCA — varianza explicada", level=2)]
n_used = pca.get("n_rows_used")
n_feat = pca.get("n_features")
intro = (
f"El {_term(mark_term, 'pca', 'PCA')} resume {_fmt_num(n_feat)} variables "
"numéricas en componentes ortogonales ordenados por la varianza que "
f"capturan ({_fmt_num(n_used)} filas usadas tras eliminar nulos). El "
"gráfico de sedimentación (scree) muestra cuánta varianza aporta cada "
"componente y su acumulado: un codo marca cuántos componentes bastan."
)
blocks.append(model.Markdown(text=intro))
scree = _make_scree(pca)
if scree is not None:
blocks.append(model.Figure(
make=scree, caption="Varianza explicada y acumulada por componente."))
evr = pca.get("explained_variance_ratio") or []
cum = pca.get("cumulative") or []
rows = []
for i, v in enumerate(evr):
acc = cum[i] if i < len(cum) else None
rows.append([f"PC{i + 1}", _fmt_pct_ratio(v), _fmt_pct_ratio(acc)])
if rows:
blocks.append(model.DataTable(
header=["Componente", "Varianza", "Acumulada"], rows=rows,
title="Varianza por componente"))
# Top loadings: keep the strongest features per component (capped).
loadings = pca.get("top_loadings") or []
if loadings:
per_comp: dict = {}
for ld in loadings:
if not _is_dict(ld):
continue
comp = ld.get("component")
per_comp.setdefault(comp, [])
if len(per_comp[comp]) < 4:
per_comp[comp].append(ld)
rows = []
for comp in sorted(per_comp.keys(), key=lambda x: (x is None, x)):
for ld in per_comp[comp]:
rows.append([f"PC{int(comp) + 1}" if comp is not None else "",
model._safe_str(ld.get("feature")),
_fmt_num(ld.get("loading"))])
if rows:
blocks.append(model.DataTable(
header=["Componente", "Variable", "Carga"], rows=rows,
title="Cargas principales (top por componente)",
note="Cargas con mayor valor absoluto: qué variables definen "
"cada eje."))
return blocks
def _kmeans_section(kmeans: dict, projection: dict, titles,
gloss=None, mark_term: bool = False) -> list:
has_km = _is_dict(kmeans) and kmeans.get("best_k")
has_proj = _is_dict(projection) and projection.get("points")
if not has_km and not has_proj:
return []
_register(gloss, "kmeans")
_register(gloss, "silhouette")
blocks = [model.Heading(text="Segmentación (KMeans)", level=2)]
best_k = (projection or {}).get("best_k") or (kmeans or {}).get("best_k")
sil = (projection or {}).get("silhouette")
if sil is None:
sil = (kmeans or {}).get("silhouette")
t_kmeans = _term(mark_term, "kmeans", "KMeans")
t_sil = _term(mark_term, "silhouette", "*silhouette*")
intro = (
f"{t_kmeans} agrupa las filas en **{_fmt_num(best_k)} segmentos** "
f"elegidos automáticamente maximizando el coeficiente de {t_sil} "
f"(**{_fmt_num(sil)}**, rango 1 a 1: cuanto más alto, segmentos más "
"compactos y separados). Los segmentos se proyectan sobre el plano de "
"los dos primeros componentes principales para visualizarlos."
)
blocks.append(model.Markdown(text=intro))
if has_proj:
scatter = _make_cluster_scatter(projection)
if scatter is not None:
blocks.append(model.Figure(
make=scatter,
caption="Cada punto es una fila coloreada por su segmento "
"KMeans; las «X» son los centroides."))
else:
blocks.append(model.Note(
"Proyección de clusters no dibujable (puntos y etiquetas "
"desalineados)."))
else:
# We have kmeans stats but no aligned points+labels to colour by.
blocks.append(model.Note(
"Scatter coloreado por segmento no disponible: el perfil no incluye "
"la proyección con etiquetas alineadas (pásala en "
"ctx['cluster_projection'] o las columnas crudas en "
"ctx['raw_numeric'] para colorear el plano PCA)."))
# Cluster sizes table.
sizes = (projection or {}).get("cluster_sizes") or (kmeans or {}).get("cluster_sizes") or []
total = sum(s for s in sizes if isinstance(s, (int, float))) or 0
if sizes:
rows = []
for i, s in enumerate(sizes):
pct = (s / total) if total else None
rows.append([f"Cluster {i}", _fmt_num(s), _fmt_pct_ratio(pct)])
blocks.append(model.DataTable(
header=["Segmento", "Tamaño", "% del total"], rows=rows,
title="Tamaño de cada segmento"))
# Per-cluster LLM micro-analysis (each entry kept indivisible as one block).
if titles:
blocks.append(model.Heading(text="Interpretación de los segmentos",
level=3))
for t in titles:
if not _is_dict(t):
continue
cid = t.get("cluster")
title = model._safe_str(t.get("title")) or f"Cluster {cid}"
desc = model._safe_str(t.get("description"))
line = f"**Cluster {cid}{title}.**"
if desc:
line += " " + desc
blocks.append(model.Markdown(text=line))
return blocks
def _outliers_section(outliers: dict, gloss=None, mark_term: bool = False) -> list:
if not _is_dict(outliers) or outliers.get("n_outliers") is None:
return []
if outliers.get("note") and not outliers.get("n_rows_used"):
# insufficient data — nothing meaningful to show.
return []
_register(gloss, "isolation_forest")
blocks = [model.Heading(text="Detección de anomalías (Isolation Forest)",
level=2)]
isof = _term(mark_term, "isolation_forest", "**Isolation Forest**")
explain = (
f"{isof} detecta filas anómalas de forma *multivariante*: "
"construye árboles que parten el espacio con cortes aleatorios y mide "
"cuántos cortes hacen falta para aislar cada fila. Las filas raras "
"(combinaciones de valores poco frecuentes considerando **todas las "
"columnas a la vez**, no una sola) se aíslan con muy pocos cortes y "
"obtienen un score bajo. El **umbral** de decisión separa las filas "
"normales de las anómalas según la contaminación esperada del modelo: "
"una fila es outlier cuando su score queda por debajo de ese umbral."
)
blocks.append(model.Markdown(text=explain))
blocks.append(model.KVTable(rows=[
("Filas analizadas", _fmt_num(outliers.get("n_rows_used"))),
("Outliers detectados", _fmt_num(outliers.get("n_outliers"))),
("% outliers", _fmt_pct_already(outliers.get("outlier_pct"))),
("Umbral de decisión", _fmt_num(outliers.get("threshold"), 4)),
], title="Anomalías multivariantes"))
return blocks
def _normality_section(normality: dict) -> list:
if not _is_dict(normality) or not normality:
return []
header = ["Columna", "Jarque-Bera (p)", "D'Agostino (p)", "Shapiro (p)",
"¿Normal?"]
rows = []
for col, res in normality.items():
if not _is_dict(res):
continue
jb = res.get("jarque_bera") if _is_dict(res.get("jarque_bera")) else {}
da = res.get("dagostino") if _is_dict(res.get("dagostino")) else {}
sh = res.get("shapiro") if _is_dict(res.get("shapiro")) else {}
is_norm = res.get("is_normal")
if res.get("note") and is_norm is None and not jb:
rows.append([model._safe_str(col), "", "", "",
model._safe_str(res.get("note"))])
continue
rows.append([
model._safe_str(col),
_fmt_num(jb.get("p"), 4) if jb else "",
_fmt_num(da.get("p"), 4) if da else "",
_fmt_num(sh.get("p"), 4) if sh else "",
"" if is_norm else ("no" if is_norm is not None else ""),
])
if not rows:
return []
return [
model.Heading(text="Normalidad de las variables", level=2),
model.Markdown(text=(
"Tests de hipótesis de normalidad por columna (hipótesis nula: la "
"muestra proviene de una distribución normal). Se marca **normal** "
"cuando el p-valor supera 0,05 (no se rechaza la nula). Pocas "
"variables reales son estrictamente normales; esto orienta qué "
"transformaciones o tests robustos aplicar después.")),
model.DataTable(header=header, rows=rows,
title="Pruebas de normalidad"),
]
# --------------------------------------------------------------------------- #
# Entry point.
# --------------------------------------------------------------------------- #
def build_modelos(profile: dict, ctx: dict):
"""Build the MODELOS Chapter, or None if there are no models to show."""
profile = profile or {}
ctx = ctx or {}
if not isinstance(profile, dict):
return None
models = profile.get("models")
if not _is_dict(models):
return None
pca = models.get("pca") if _is_dict(models.get("pca")) else None
kmeans = models.get("kmeans") if _is_dict(models.get("kmeans")) else None
outliers = models.get("outliers") if _is_dict(models.get("outliers")) else None
normality = models.get("normality") if _is_dict(models.get("normality")) else None
projection, _src = _resolve_cluster_projection(profile, ctx)
titles = _cluster_titles(profile, ctx, projection) if (
(kmeans and kmeans.get("best_k")) or (projection and projection.get("points"))
) else None
# Shared glossary collector: terms are registered + marked clickable inside
# each section, only when that section actually renders (no orphan entries).
glossary = ctx.get("glossary")
gloss = glossary if isinstance(glossary, model.GlossaryCollector) else None
mark_term = gloss is not None
sections = []
sections += _pca_section(pca, gloss, mark_term) if pca else []
sections += _kmeans_section(kmeans, projection, titles, gloss, mark_term)
sections += _outliers_section(outliers, gloss, mark_term) if outliers else []
sections += _normality_section(normality) if normality else []
if not sections:
return None # models block present but nothing renderable.
blocks = _normalization_intro(gloss, mark_term) + sections
return model.Chapter(id=CHAPTER_ID, title=CHAPTER_TITLE,
version=CHAPTER_VERSION, blocks=blocks)