Write a Python function to calculate the sample standard deviation of an array of numbers. (Don't use any prewritten standard deviation functions).
system
sankhyaon ke ek sarani ke namoona maanak vichlan kii gananaa karne ke liye ek paythan fnction likhen.(kisi bhi purvavarti maanak vichlan kaaryon kaa upyog na karen).
user
yahaan namoona maanak vichlan kii gananaa karne ke liye ek fnction he, jise kharonch se likhaa gaya he:

DEF STDEV (NUMS):
    madhya = yoga (sankhya) / len (sankhya)
    diffs = [(num - mean) ** 2 num main sankhya ke liye]
    math. SQRT (SUM (diffs) / (len (nums) - 1)
assistant
<|system|>
</s>
<|user|>
sankhyaon ke ek sarani ke namoona maanak vichlan kii gananaa karne ke liye ek paythan fnction likhen.(kisi bhi purvavarti maanak vichlan kaaryon kaa upyog na karen).</s>
<|assistant|>
yahaan namoona maanak vichlan kii gananaa karne ke liye ek fnction he, jise kharonch se likhaa gaya he:

DEF STDEV (NUMS):
    madhya = yoga (sankhya) / len (sankhya)
    diffs = [(num - mean) ** 2 num main sankhya ke liye]
    math. SQRT (SUM (diffs) / (len (nums) - 1)</s>
