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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:
 http
Step1:  pre-defined colors
signal => blue
trend => 
trend-residue => red
cycle => yellow
cycle-residue => red
ar => 
ar-residue => red
forecast => green
upper-bound , lower-bound , shaded-area => green, green, light-blue
ticks on left and right sides.
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Python Code:
df.plot.line('Time' , ['Sig1', 'Sig2', 'Sig3'], color=['c' , 'm' , 'y']) 
df.plot.line('Time' , ['Sig1', 'Sig2', 'Sig3'], color=['#800000' , '#008000' , '#000080']) 
Explanation: http://matplotlib.org/api/colors_api.html
Commands which take color arguments can use several formats to specify the colors. For the basic built-in colors, you can use a single letter
    b: blue
    g: green
    r: red
    c: cyan
    m: magenta
    y: yellow
    k: black
    w: white
End of explanation
df.plot.line('Time' , ['Sig1', 'Sig2', 'Sig3'], color=['r' , 'g' , 'b']) 
Explanation: pre-defined colors
signal => blue
trend => 
trend-residue => red
cycle => yellow
cycle-residue => red
ar => 
ar-residue => red
forecast => green
upper-bound , lower-bound , shaded-area => green, green, light-blue
ticks on left and right sides.
End of explanation
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