! LaTeX 错误：缺少 \begin{document}。IEEE

Question

我的代码有问题，我见过类似的帖子但没有任何帮助，我在 Texmaker 中使用 biber % 和 pdf+bilatex+pdflatex+pdf，有什么建议吗？

谢谢

代码：

\documentclass[conference]{IEEEtran}
xxxx\IEEEoverridecommandlockouts
% The preceding line is only needed to identify funding in the first footnote. If that is unneeded, please comment it out.
\usepackage[backend=biber, bibencoding=utf8,defernumbers=true]{biblatex}
\usepackage[T1]{fontenc}
\let\proof\relax
\let\endproof\relax
\usepackage{amsmath,amssymb,amsfonts}
\usepackage{algorithmic}
\usepackage{multirow}
\usepackage{textcomp}
\usepackage{lscape}
\usepackage{xcolor}
\def\BibTeX{{\rm B\kern-.05em{\sc i\kern-.025em b}\kern-.08em
    T\kern-.1667em\lower.7ex\hbox{E}\kern-.125emX}}
\usepackage{graphicx}

\usepackage[colorlinks,allcolors=blue]{hyperref}
\usepackage[titles]{tocloft}

\addbibresource{biblio.bib}

\begin{document}
...
\end{document}

错误：

! LaTeX Error: Missing \begin{document}.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...