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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ynnm(n, m):

 """Initial value for recursion formula"""
 
    a = 1.0 / np.sqrt(4.0 * np.pi)
    pm = np.abs(m)

    out = 0.0

    if(n < pm):
        out = 0.0
    elif(n == 0):
        out = a
    else:
        out = a
        for k in xrange(1, n + 1):
            out *= np.sqrt((2.0 * k + 1.0) / 8.0 / k)

        if(n != pm):
            for k in xrange(n - 1, pm - 1, -1):
                out *= np.sqrt((n + k + 1.0) / (n - k))
    return out