Cheeky comment aside, PyPy is an alternative interpreter for Python and, more broadly, a meta-frame work to make writing tracing JIT for the language of your choice easy.
It's much faster than regular Python. The only downside (which, admittedly, is very, very big) is that the PyPy developers released their own FFI library for interfacing with C-code (which works brilliantly), but using c-types and the c-python c-api is very kludgy. This means that a lot of very important python libraries which are basically thin wrappers around c/fortran code (SciPy, NumPy, etc) are not really working.
There is some effort around reimplementing NumPy in PyPy, but it's going very slowly.
Edit:
PyPy is also a heroic effort by a small team of developers who receive some donations. JS is probably the language that received the most amount of money and attention into making it run fast from Google/Mozilla, etc - in terms of results/money, PyPy is incredible.
To be a bit more specific, pypy can be much faster, for certain usecases. For others it may not be, or it may be even significanlty slower - writing JIT for python is not an easy task.
Cheeky comment aside, PyPy is an alternative interpreter for Python and, more broadly, a meta-frame work to make writing tracing JIT for the language of your choice easy.
It's much faster than regular Python. The only downside (which, admittedly, is very, very big) is that the PyPy developers released their own FFI library for interfacing with C-code (which works brilliantly), but using c-types and the c-python c-api is very kludgy. This means that a lot of very important python libraries which are basically thin wrappers around c/fortran code (SciPy, NumPy, etc) are not really working.
There is some effort around reimplementing NumPy in PyPy, but it's going very slowly.
Edit: PyPy is also a heroic effort by a small team of developers who receive some donations. JS is probably the language that received the most amount of money and attention into making it run fast from Google/Mozilla, etc - in terms of results/money, PyPy is incredible.