code: def iscollection(ds):
      """Is a collection of items, has dimension
  
      >>> iscollection('5 * int32')
      True
      >>> iscollection('int32')
      False
      """
      if isinstance(ds, str):
          ds = dshape(ds)
      return isdimension(ds[0])
  
file_path: datashader/datashader/datashape/predicates.py
imports: import numpy
  from .util import collect, dshape
  from .internal_utils import remove
  from .coretypes import DataShape, Fixed, Var, Ellipsis, Record, Unit, date_, datetime_, TypeVar, to_numpy_dtype, Categorical
  from .typesets import floating, boolean
label_desc: Use image node_id 8 for calling a global function with example usage: iscollection(ds) and returns: isdimension