dir(x) for that weird type

dir_x

sage: dir(polygen(RR))

['N',
 '__add__',
 '__call__',
 '__class__',
 '__cmp__',
 '__copy__',
 '__delattr__',
 '__delitem__',
 '__dict__',
 '__dir__',
 '__div__',
 '__doc__',
 '__eq__',
 '__float__',
 '__floordiv__',
 '__format__',
 '__ge__',
 '__getattribute__',
 '__getitem__',
 '__getmetaclass__',
 '__getstate__',
 '__gt__',
 '__hash__',
 '__init__',
 '__int__',
 '__invert__',
 '__iter__',
 '__le__',
 '__long__',
 '__lshift__',
 '__lt__',
 '__mod__',
 '__module__',
 '__mul__',
 '__ne__',
 '__neg__',
 '__new__',
 '__nonzero__',
 '__pari__',
 '__pos__',
 '__pow__',
 '__pyx_vtable__',
 '__radd__',
 '__rdiv__',
 '__reduce__',
 '__reduce_ex__',
 '__repr__',
 '__rfloordiv__',
 '__rlshift__',
 '__rmod__',
 '__rmul__',
 '__rpow__',
 '__rrshift__',
 '__rshift__',
 '__rsub__',
 '__rtruediv__',
 '__rxor__',
 '__setattr__',
 '__setitem__',
 '__setstate__',
 '__sizeof__',
 '__str__',
 '__sub__',
 '__subclasshook__',
 '__truediv__',
 '__weakref__',
 '__xor__',
 '_act_on_',
 '_acted_upon_',
 '_add_',
 '_add_parent',
 '_ascii_art_',
 '_asin_series',
 '_asinh_series',
 '_atan_series',
 '_atanh_series',
 '_axiom_',
 '_axiom_init_',
 '_cache_key',
 '_cmp_',
 '_coeff_repr',
 '_compile',
 '_cos_series',
 '_cosh_series',
 '_derivative',
 '_div_',
 '_doccls',
 '_dummy_attribute',
 '_exp_series',
 '_factor_pari_helper',
 '_fast_callable_',
 '_fast_float_',
 '_floordiv_',
 '_fricas_',
 '_fricas_init_',
 '_gap_',
 '_gap_init_',
 '_get_compiled',
 '_giac_',
 '_giac_init_',
 '_gp_',
 '_gp_init_',
 '_im_gens_',
 '_integer_',
 '_interface_',
 '_interface_init_',
 '_interface_is_cached_',
 '_is_atomic',
 '_kash_',
 '_kash_init_',
 '_latex_',
 '_latex_coeff_repr',
 '_lcm',
 '_libgap_',
 '_lmul_',
 '_log_series',
 '_macaulay2_',
 '_macaulay2_init_',
 '_magma_init_',
 '_maple_',
 '_maple_init_',
 '_mathematica_',
 '_mathematica_init_',
 '_maxima_',
 '_maxima_init_',
 '_maxima_lib_',
 '_maxima_lib_init_',
 '_mpmath_',
 '_mpoly_dict_recursive',
 '_mul_',
 '_mul_fateman',
 '_mul_generic',
 '_mul_karatsuba',
 '_mul_parent',
 '_mul_trunc',
 '_mul_trunc_',
 '_neg_',
 '_new_constant_poly',
 '_octave_',
 '_octave_init_',
 '_pari_',
 '_pari_init_',
 '_pari_or_constant',
 '_pari_with_name',
 '_polymake_',
 '_polymake_init_',
 '_pow',
 '_pow_',
 '_pow_naive',
 '_power_trunc',
 '_r_init_',
 '_rational_',
 '_reduction',
 '_repr',
 '_repr_',
 '_richcmp_',
 '_rmul_',
 '_roots_from_factorization',
 '_sage_',
 '_sage_input_',
 '_set_parent',
 '_sin_series',
 '_singular_',
 '_singular_init_',
 '_sinh_series',
 '_sub_',
 '_symbolic_',
 '_tan_series',
 '_tanh_series',
 '_test_category',
 '_test_eq',
 '_test_new',
 '_test_nonzero_equal',
 '_test_not_implemented_methods',
 '_test_pickling',
 '_tester',
 '_unicode_art_',
 'abs',
 'adams_operator',
 'add_bigoh',
 'additive_order',
 'all_roots_in_interval',
 'any_root',
 'args',
 'base_extend',
 'base_ring',
 'cartesian_product',
 'category',
 'change_ring',
 'change_variable_name',
 'coefficients',
 'coeffs',
 'complex_roots',
 'compose_power',
 'compose_trunc',
 'composed_op',
 'constant_coefficient',
 'content',
 'cyclotomic_part',
 'db',
 'degree',
 'denominator',
 'derivative',
 'dict',
 'diff',
 'differentiate',
 'discriminant',
 'dispersion',
 'dispersion_set',
 'divides',
 'dump',
 'dumps',
 'euclidean_degree',
 'exponents',
 'factor',
 'gcd',
 'gradient',
 'hamming_weight',
 'homogenize',
 'integral',
 'inverse_mod',
 'inverse_of_unit',
 'inverse_series_trunc',
 'is_constant',
 'is_cyclotomic',
 'is_cyclotomic_product',
 'is_gen',
 'is_homogeneous',
 'is_idempotent',
 'is_irreducible',
 'is_monic',
 'is_monomial',
 'is_nilpotent',
 'is_one',
 'is_prime',
 'is_primitive',
 'is_real_rooted',
 'is_square',
 'is_squarefree',
 'is_term',
 'is_unit',
 'is_zero',
 'lc',
 'lcm',
 'leading_coefficient',
 'list',
 'lm',
 'lt',
 'map_coefficients',
 'mod',
 'monic',
 'monomial_coefficient',
 'monomials',
 'multiplication_trunc',
 'multiplicative_order',
 'n',
 'newton_raphson',
 'newton_slopes',
 'norm',
 'nth_root',
 'number_of_real_roots',
 'number_of_roots_in_interval',
 'number_of_terms',
 'numerator',
 'numerical_approx',
 'ord',
 'order',
 'padded_list',
 'parent',
 'plot',
 'polynomial',
 'power_trunc',
 'powers',
 'prec',
 'pseudo_quo_rem',
 'quo_rem',
 'radical',
 'real_roots',
 'rename',
 'reset_name',
 'resultant',
 'reverse',
 'root_field',
 'roots',
 'save',
 'shift',
 'specialization',
 'splitting_field',
 'sqrt',
 'square',
 'squarefree_decomposition',
 'subs',
 'substitute',
 'sylvester_matrix',
 'symmetric_power',
 'truncate',
 'truncate_abs',
 'valuation',
 'variable_name',
 'variables',
 'xgcd']