code: def _is_range(r):
      """A range is defined as (symbol, start, end). start and end should
      be numbers.
      """
      # TODO: prange check goes here
      return (
          isinstance(r, Tuple)
          and (len(r) == 3)
          and (not isinstance(r.args[1], str))
          and r.args[1].is_number
          and (not isinstance(r.args[2], str))
          and r.args[2].is_number
      )
  
file_path: sympy/sympy/plotting/utils.py
imports: from sympy.core.containers import Tuple
  from sympy.core.basic import Basic
  from sympy.core.expr import Expr
  from sympy.core.function import AppliedUndef
  from sympy.core.relational import Relational
  from sympy.core.symbol import Dummy
  from sympy.core.sympify import sympify
  from sympy.logic.boolalg import BooleanFunction
  from sympy.sets.fancysets import ImageSet
  from sympy.sets.sets import FiniteSet
  from sympy.tensor.indexed import Indexed
label_desc: Use image node_id 5 for calling a global function with example usage: _is_range(r) and returns: unknown