What is the base language Python is written in?
it is written in C, its also called CPython.
You get a good idea if you compile python from source. Usually it's gcc
that compiles the *.c
files
To add to and reframe some of the other good answers:
The specification for Python (question) is written in English, but could be written in a formal semantics, as Standard ML and Scheme are. See Programming language specification.
There are implementations of Python in many languages, as noted by Gandaro, of which the fastest is surprisingly not the original CPython, which is written in C.
Python is written in English. But there are several implementations:
You can't say that Python is written in some programming language, since Python as a language is just a set of rules (like syntax rules, or descriptions of standard functionality). So we might say, that it is written in English :). However, mentioned rules can be implemented in some programming language. Hence, if you send a string like 'import this' to that program called interpreter, it'd return you "Zen of Python".
Since most modern OS are written in C, compilers/interpreters for modern high-level languages are also written in C. Python is not an exception - its most popular/"traditional" implementation is called CPython and is written in C.
There are other implementations:
The sources are public. Python is written in C (actually the default implementation is called CPython).