Bonds not displayed about chanim HOT 3 CLOSED

\documentclass[preview]{standalone}

\usepackage[english]{babel}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{dsfont}
\usepackage{setspace}
\usepackage{tipa}
\usepackage{relsize}
\usepackage{textcomp}
\usepackage{mathrsfs}
\usepackage{calligra}
\usepackage{wasysym}
\usepackage{ragged2e}
\usepackage{physics}
\usepackage{xcolor}
\usepackage{microtype}
\usepackage{tikz}
\usetikzlibrary{arrows}
\usetikzlibrary{shapes.geometric}
\usepackage{chemfig}
\usepackage{mhchem}
\DisableLigatures{encoding = *, family = * }
%\usepackage[UTF8]{ctex}
\linespread{1}

\begin{document}

\begin{align*}
\setchemfig{atom sep = 2em}
\chemfig{-[:30](=[2]O)-[:-30]OH}
\end{align*}

\end{document}

from manimlib.imports import *

class TikzMobject(TextMobject):
    CONFIG = {
        "stroke_width": 3,
        "fill_opacity": 0,
        "stroke_opacity": 1,
    }

class ExampleTikz(Scene):
    def construct(self):
        circuit = TikzMobject(r"""
            \begin{tikzpicture}
                \draw (0,0) -- (1,0);
                \node at (1,0) {sometext};
            \end{tikzpicture}
            """
            )
        self.play(Write(circuit))
        self.wait()