quick fix

Author: Aron Fischer

example_scenes/customtex.py

@@ -34,7 +34,7 @@ def construct(self):
         myTemplate.tex_compiler = "pdflatex"
         myTemplate.output_format = ".pdf"
 
-        # To use this template in a Tex() or MathTex object
+        # To use this template in a Tex() or MathTex() object
         # use the keyword argument tex_template
         text = MathTex(r"\vv{vb}", tex_template=myTemplate)
         self.play(Write(text))

manim/utils/tex.py

@@ -172,10 +172,7 @@ def rebuild(self):
     def file_not_mutable():
         raise Exception("Cannot modify TexTemplate when using a template file.")
 
-    def prepend_to_preamble(self, txt):
-        self.file_not_mutable()
-
-    def add_to_preamble(self, txt):
+    def add_to_preamble(self, txt, prepend=False):
         self.file_not_mutable()
 
     def add_to_document(self, txt):