legacy unified language for form-compilers (Python 3)

 UFL (Unified Form Language) is a unified language for definition of
 variational forms intended for finite element discretization. More
 precisely, it defines a fixed interface for choosing finite element
 spaces and defining expressions for weak forms in a notation close to
 mathematical notation. The form compilers FFC and SyFi use UFL as
 their end-user interface, producing UFC implementations as their
 output.
 .
 This package installs the legacy (2022) library for Python 3 used by
 the legacy FEniCS packages ffc and dolfin. The python package is
 renamed ufl_legacy rather than ufl.