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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:
 <br/><br/><br/><br/><br/>
<br/><br/><br/><br/>
todo
- [] Date Filter or Geo Filter Function
- [] carto-python
- [] colorbar - value - same range
       - For now, scale values to [0,1]
       - x_new = (x-min)/(max-min)
- [] Any record with 'NaN' bssid or ssid
- [] Check API - directly connect API - API query -&gt; process -&gt; plot
<br/>
done
- [] Check max # of unique bsside 
Step1:  2. free wifi
Step2:  DataFrame
Step3:  <br/><br>
Check
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Python Code:
m
Explanation: <br/><br/><br/><br/><br/>
<br/><br/><br/><br/>
todo
- [] Date Filter or Geo Filter Function
- [] carto-python
- [] colorbar - value - same range
       - For now, scale values to [0,1]
       - x_new = (x-min)/(max-min)
- [] Any record with 'NaN' bssid or ssid
- [] Check API - directly connect API - API query -&gt; process -&gt; plot
<br/>
done
- [] Check max # of unique bsside : 200+
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1. All wifi
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n
Explanation: 2. free wifi
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# m
grid_plot.sort_values(ascending=False, by='uni').head()
# n
freeGrid2.sort_values(ascending=False, by='median level').head()
Explanation: DataFrame
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check1 = grid_bssid.dropna(subset=['unique_bssid_list']).sort_values(ascending=False, by='uni').head().iloc[0,3]
len(check1)
Explanation: <br/><br>
Check
End of explanation
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