Erreur with date metadata

[djangoliv]

I can't export simple notebook in pdf with date in metadata.

The conversion fail with the following example:

{
 "cells": [
 ],
 "metadata": {
  "date": 1704808220.9683206
},
 "nbformat": 4,
 "nbformat_minor": 5
}

Traceback:

$ jupyter nbconvert --to pdf example.ipynb

 
[NbConvertApp] Converting notebook to_start.fr.ipynb to pdf
Traceback (most recent call last):
  File "/tmp/yy/bin/jupyter-nbconvert", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/jupyter_core/application.py", line 283, in launch_instance
    super().launch_instance(argv=argv, **kwargs)
  File "/tmp/yy/lib/python3.11/site-packages/traitlets/config/application.py", line 1075, in launch_instance
    app.start()
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/nbconvertapp.py", line 420, in start
    self.convert_notebooks()
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/nbconvertapp.py", line 597, in convert_notebooks
    self.convert_single_notebook(notebook_filename)
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/nbconvertapp.py", line 563, in convert_single_notebook
    output, resources = self.export_single_notebook(
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/nbconvertapp.py", line 487, in export_single_notebook
    output, resources = self.exporter.from_filename(
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/exporters/templateexporter.py", line 386, in from_filename
    return super().from_filename(filename, resources, **kw)  # type:ignore[return-value]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/exporters/exporter.py", line 201, in from_filename
    return self.from_file(f, resources=resources, **kw)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/exporters/templateexporter.py", line 392, in from_file
    return super().from_file(file_stream, resources, **kw)  # type:ignore[return-value]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/exporters/exporter.py", line 220, in from_file
    return self.from_notebook_node(
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/exporters/pdf.py", line 184, in from_notebook_node
    latex, resources = super().from_notebook_node(nb, resources=resources, **kw)
                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/exporters/latex.py", line 92, in from_notebook_node
    return super().from_notebook_node(nb, resources, **kw)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/exporters/templateexporter.py", line 424, in from_notebook_node
    output = self.template.render(nb=nb_copy, resources=resources)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/jinja2/environment.py", line 1301, in render
    self.environment.handle_exception()
  File "/tmp/yy/lib/python3.11/site-packages/jinja2/environment.py", line 936, in handle_exception
    raise rewrite_traceback_stack(source=source)
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/index.tex.j2", line 8, in top-level template code
    ((* extends cell_style *))
    ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/style_jupyter.tex.j2", line 176, in top-level template code
    \prompt{(((prompt)))}{(((prompt_color)))}{(((execution_count)))}{(((extra_space)))}
    ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/base.tex.j2", line 7, in top-level template code
    ((*- extends 'document_contents.tex.j2' -*))
    ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/document_contents.tex.j2", line 51, in top-level template code
    ((*- block figure scoped -*))
    ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/display_priority.j2", line 5, in top-level template code
    ((*- extends 'null.j2' -*))
    ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/null.j2", line 28, in top-level template code
    ((*- block header -*))
    ^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/base.tex.j2", line 98, in block 'header'
    ((* block definitions *))
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/style_jupyter.tex.j2", line 11, in block 'definitions'
    ((( super() )))
^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/base.tex.j2", line 185, in block 'definitions'
    ((* block date *))
^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/share/jupyter/nbconvert/templates/latex/base.tex.j2", line 187, in block 'date'
    \date{((( nb.metadata.date | escape_latex )))}
^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/yy/lib/python3.11/site-packages/nbconvert/filters/latex.py", line 57, in escape_latex
    text = "".join(LATEX_SUBS.get(c, c) for c in text)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: 'float' object is not iterable

Regards