class_docstr: Class to denote a base vector.
class_docstr_tok: ["Class","to","denote","a","base","vector","."]
code: def _sympyrepr(self, printer):
      index, system = self._id
      return printer._print(system) + "." + system._vector_names[index]
  
imports: from __future__ import annotations
  from itertools import product
  from sympy.core.add import Add
  from sympy.core.assumptions import StdFactKB
  from sympy.core.expr import AtomicExpr, Expr
  from sympy.core.power import Pow
  from sympy.core.singleton import S
  from sympy.core.sorting import default_sort_key
  from sympy.core.sympify import sympify
  from sympy.functions.elementary.miscellaneous import sqrt
  from sympy.matrices.immutable import ImmutableDenseMatrix
  from sympy.vector.basisdependent import BasisDependentZero, BasisDependent, BasisDependentMul, BasisDependentAdd
  from sympy.vector.coordsysrect import CoordSys3D
  from sympy.vector.dyadic import Dyadic, BaseDyadic, DyadicAdd
label_desc: Use image node_id 4 for calling the BaseVector obj's underlying member method code with example usage: obj._sympyrepr(printer) and returns: unknown