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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 In this post, we'll look at a couple of statistics functions in Python. These statistics functions are part of the Python Standard Library in the statistics module. The four functions we'll use in this post are common in statistics
Step1:  Calculate the mean
To calculate the mean, or average of our test scores, use the statistics module's mean() function.
Step2:  Calculate the median
To calculate the median, or middle value of our test scores, use the statistics module's median() function. 
If there are an odd number of values, median() returns the middle value. If there are an even number of values median() returns an average of the two middle values.
Step3:  Calculate the mode
To calculate the mode, or most often value of our test scores, use the statistics module's mode() function. 
If there is more than one number which occurs most often, mode() returns an error. 
```python
mode([1, 1, 2, 2, 3])
StatisticsError
Step4:  Calculate the standard deviation
To calculate the standard deviation, or spread of the test scores, use the statistics module's stdev() function. A large standard deviation indicates the data is spread out; a small standard deviation indicates the data is clustered close together.
Step5:  Alternatively, we can import the whole statistics module at once (all the functions in the staticsitics module) using the the line
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Python Code:
from statistics import mean, median, mode, stdev
test_scores = [60 , 83, 83, 91, 100]
Explanation: In this post, we'll look at a couple of statistics functions in Python. These statistics functions are part of the Python Standard Library in the statistics module. The four functions we'll use in this post are common in statistics:
mean - average value
median - middle value
mode - most often value
standard deviation - spread of values
To access Python's statistics functions, we need to import the functions from the statistics module using the statement: 
python
from statistics import mean, median, mode, stdev
After the import statement, the functions mean(), median(), mode() and stdev()(standard deviation) can be used. Since the statistics module is part of the Python Standard Library, no external packages need to be installed.
Let's imagine we have a data set of 5 test scores. The test scores are 60, 83, 91 and 100. These test scores can be stored in a Python list. Python lists are defined with square brackets [ ]. Elements in Python lists are separated with commas.
End of explanation
mean(test_scores)
Explanation: Calculate the mean
To calculate the mean, or average of our test scores, use the statistics module's mean() function.
End of explanation
median(test_scores)
83
Explanation: Calculate the median
To calculate the median, or middle value of our test scores, use the statistics module's median() function. 
If there are an odd number of values, median() returns the middle value. If there are an even number of values median() returns an average of the two middle values.
End of explanation
mode(test_scores)
Explanation: Calculate the mode
To calculate the mode, or most often value of our test scores, use the statistics module's mode() function. 
If there is more than one number which occurs most often, mode() returns an error. 
```python
mode([1, 1, 2, 2, 3])
StatisticsError: no unique mode; found 2 equally common values
```
If there is no value that occurs most often (all the values are unique or occur the same number of times), mode() also returns an error.
```python
mode([1,2,3])
StatisticsError: no unique mode; found 3 equally common values
```
End of explanation
stdev(test_scores)
Explanation: Calculate the standard deviation
To calculate the standard deviation, or spread of the test scores, use the statistics module's stdev() function. A large standard deviation indicates the data is spread out; a small standard deviation indicates the data is clustered close together.
End of explanation
import statistics
test_scores = [60 , 83, 83, 91, 100]
statistics.mean(test_scores)
statistics.median(test_scores)
statistics.mode(test_scores)
statistics.stdev(test_scores)
Explanation: Alternatively, we can import the whole statistics module at once (all the functions in the staticsitics module) using the the line:
python
import statistics
Then to use the functions from the module, we need to call the names statistics.mean(), statistics.median(), statistics.mode(), and statistics.stdev(). See below:
End of explanation
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