code: def _dup_left_decompose(f, h, K):
      """Helper function for :func:`_dup_decompose`."""
      g, i = {}, 0
  
      while f:
          q, r = dup_div(f, h, K)
  
          if dup_degree(r) > 0:
              return None
          else:
              g[i] = dup_LC(r, K)
              f, i = q, i + 1
  
      return dup_from_raw_dict(g, K)
  
imports: from sympy.polys.densearith import dup_add_term, dmp_add_term, dup_lshift, dup_add, dmp_add, dup_sub, dmp_sub, dup_mul, dmp_mul, dup_sqr, dup_div, dup_rem, dmp_rem, dmp_expand, dup_mul_ground, dmp_mul_ground, dup_quo_ground, dmp_quo_ground, dup_exquo_ground, dmp_exquo_ground
  from sympy.polys.densebasic import dup_strip, dmp_strip, dup_convert, dmp_convert, dup_degree, dmp_degree, dmp_to_dict, dmp_from_dict, dup_LC, dmp_LC, dmp_ground_LC, dup_TC, dmp_TC, dmp_zero, dmp_ground, dmp_zero_p, dup_to_raw_dict, dup_from_raw_dict, dmp_zeros
  from sympy.polys.polyerrors import MultivariatePolynomialError, DomainError
  from sympy.utilities import variations
  from math import ceil, log
label_desc: Use image node_id 36 for calling a global function with example usage: _dup_left_decompose(f, h, K) and returns: dup_from_raw_dict, None