code: def is_uniform_reindex(join_units):
      return (
          # TODO: should this be ju.block._can_hold_na?
          all(ju.block and ju.block.is_extension for ju in join_units)
          and len({ju.block.dtype.name for ju in join_units}) == 1
      )
  
imports: from collections import defaultdict
  import copy
  import numpy
  from pandas._libs import internals, tslibs
  from pandas.util._decorators import cache_readonly
  from pandas.core.dtypes.cast import maybe_promote
  from pandas.core.dtypes.common import _get_dtype, is_categorical_dtype, is_datetime64_dtype, is_datetime64tz_dtype, is_extension_array_dtype, is_float_dtype, is_numeric_dtype, is_sparse, is_timedelta64_dtype
  import pandas.core.dtypes.concat
  from pandas.core.dtypes.missing import isna
  import pandas.core.algorithms
label_desc: Use image node_id 5 for calling a global function with example usage: is_uniform_reindex(join_units) and returns: unknown