human
Solve the following python programming problem given the following code:
@ defun 
def pcfw(ctx, a, z, **kwargs) : 
    '
    Gives the parabolic cylinder function `W(a,z)` defined in (DLMF 12.14).

    **Examples**

    Value at the origin::

        >>> from mpmath import *
        >>> mp.dps = 25.
mp.pretty = True
        >>> a = mpf(0.25)
        >>> pcfw(a,0)
        0.9722833245718180765617104
        >>> power(2,-0.75)*sqrt(abs(gamma(0.25+0.5j*a)/gamma(0.75+0.5j*a)))
        0.9722833245718180765617104
        >>> diff(pcfw,(a,0),(0,1))
        -0.5142533944210078966003624
        >>> -power(2,-0.25)*sqrt(abs(gamma(0.75+0.5j*a)/gamma(0.25+0.5j*a)))
        -0.5142533944210078966003624

    ' 
    (n, _) = ctx._convert_param (a) 
    z = ctx.convert (z) 
    def terms() : 
        phi2 = ctx.arg (ctx.gamma ((0.5 + (ctx.j * n)))) 
        phi2 = ((ctx.loggamma ((0.5 + (ctx.j * n))) - ctx.loggamma ((0.5 - (ctx.j * n)))) / 2j) 
        rho = ((ctx.pi / 8) + (0.5 * phi2)) 
        k = (ctx.sqrt ((1 + ctx.exp (((2 * ctx.pi) * n)))) - ctx.exp ((ctx.pi * n))) 
        C = (ctx.sqrt ((k / 2)) * ctx.exp (((0.25 * ctx.pi) * n))) 
        (yield ((C * ctx.expj (rho)) * ctx.pcfu ((ctx.j * n), (z * ctx.expjpi ((- 0.25)))))) 
        (yield ((C * ctx.expj ((- rho))) * ctx.pcfu (((- ctx.j) * n), (z * ctx.expjpi (0.25))))) 
v = ctx.sum_accurately (terms) 
    if (ctx._is_real_type (_) and ctx._is_real_type (z)) : 
        v = ctx._re (v) 
return v 

    
    

    Fix the buggy line: if (ctx._is_real_type (_) and ctx._is_real_type (z)) :
assistant
#Here is Python program to fix the buggy line: if (ctx.

if (ctx._is_real_type (n) and ctx._is_real_type (z)) :