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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:
 tsgettoolbox and tstoolbox - Python Programming Interface
'tsgettoolbox nwis ...'
Step1:  Let's say that I want flow (parameterCd=00060) for site '02325000'.  All of the tsgettoolbox functions create a pandas DataFrame.
Step2:  'tstoolbox ...'
Step3:  'tstoolbox plot' has many options that can be used to modify the plot.
Step4:  
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Python Code:
%matplotlib inline
from tsgettoolbox import tsgettoolbox
Explanation: tsgettoolbox and tstoolbox - Python Programming Interface
'tsgettoolbox nwis ...': Download data from the National Water Information System (NWIS)
This notebook is to illustrate the Python API usage for 'tsgettoolbox' to download and work with data from the National Water Information System (NWIS).  There is a different notebook to do the same things from the command line called tsgettoolbox-nwis-cli.  The CLI version of tsgettoolbox can be used from other languages that have the ability to make a system call.
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df = tsgettoolbox.nwis_dv(sites="02325000", startDT="2000-01-01", parameterCd="00060")
df.head()  # The .head() function gives the first 5 values of the time-series
Explanation: Let's say that I want flow (parameterCd=00060) for site '02325000'.  All of the tsgettoolbox functions create a pandas DataFrame.
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from tstoolbox import tstoolbox
tstoolbox.plot(input_ts=df, ofilename="plot_api.png")
Explanation: 'tstoolbox ...': Process data using 'tstoolbox'
Now lets use "tstoolbox" to plot the time-series.  The 'input_ts' option is used to read in the time-series from the DataFrame.
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tstoolbox.plot(
    input_ts=df,
    ofilename="flow_api.png",
    ytitle="Flow (cfs)",
    title="02325000: FENHOLLOWAY RIVER NEAR PERRY, FLA",
    legend=False,
)
Explanation: 'tstoolbox plot' has many options that can be used to modify the plot.
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mdf = tstoolbox.aggregate(input_ts=df, agg_interval="M", statistic="mean")
tstoolbox.plot(input_ts=mdf, drawstyle="steps-pre", ofilename="flow_api_monthly.png")
Explanation: 
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