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while

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Introduction
While statement execute the statement subject to condition attached. The statement could be affirmatively declared true to allow the execution. However after while any condition to could be attached to function. 

Syntax
"While" condition attached:
   "Do this' 
exception ":"
    "Do this"

Parameters
parameter could be string or numbers

Example
The turtle dot loop is generated through while statement and colors are selected through the random.sample method.
import turtle
import random

turtle.speed(100)
h=50
w=50
s.screensize(h,w)
y=r

while y > 0:
    ps=random.randrange(1,10)
    turtle.pensize(ps)

    turtle.pendown()
    y=y-1
    color_list= ['snow', 'ghostwhite', 'whitesmoke', 'gainsboro', 'floralwhite', 'oldlace',
    'linen', 'antiquewhite', 'papayawhip', 'blanchedalmond', 'bisque', 'peachpuff',
    'navajowhite', 'lemonchiffon', 'mintcream', 'azure', 'aliceblue', 'lavender',
    'lavenderblush', 'mistyrose', 'darkslategray', 'dimgray', 'slategray',
    'lightslategray', 'gray', 'lightgrey', 'midnightblue', 'navy', 'cornflowerblue', 'darkslateblue',
    'slateblue', 'mediumslateblue', 'lightslateblue', 'mediumblue', 'royalblue',  'blue',
    'dodgerblue', 'deepskyblue', 'skyblue', 'lightskyblue', 'steelblue', 'lightsteelblue',
    'lightblue', 'powderblue', 'paleturquoise', 'darkturquoise', 'mediumturquoise', 'turquoise',
    'cyan', 'lightcyan', 'cadetblue', 'mediumaquamarine', 'aquamarine', 'darkgreen', 'darkolivegreen',
    'darkseagreen', 'seagreen', 'mediumseagreen', 'lightseagreen', 'palegreen', 'springgreen',
    'lawngreen', 'mediumspringgreen', 'greenyellow', 'limegreen', 'yellowgreen',
    'forestgreen', 'olivedrab', 'darkkhaki', 'khaki', 'palegoldenrod', 'lightgoldenrodyellow',
    'lightyellow', 'yellow', 'gold', 'lightgoldenrod', 'goldenrod', 'darkgoldenrod', 'rosybrown',
    'indianred', 'saddlebrown', 'sandybrown',
    'darksalmon', 'salmon', 'lightsalmon', 'orange', 'darkorange',
    'coral', 'lightcoral', 'tomato', 'orangered', 'red', 'hotpink', 'deeppink', 'pink', 'lightpink',
    'palevioletred', 'maroon', 'mediumvioletred', 'violetred',
    'mediumorchid', 'darkorchid', 'darkviolet', 'blueviolet', 'purple', 'mediumpurple',
    'thistle', 'snow2', 'snow3',
    'snow4', 'seashell2', 'seashell3', 'seashell4', 'AntiqueWhite1', 'AntiqueWhite2',
    'AntiqueWhite3', 'AntiqueWhite4', 'bisque2', 'bisque3', 'bisque4', 'PeachPuff2',
    'PeachPuff3', 'PeachPuff4', 'NavajoWhite2', 'NavajoWhite3', 'NavajoWhite4',
    'LemonChiffon2', 'LemonChiffon3', 'LemonChiffon4', 'cornsilk2', 'cornsilk3',
    'cornsilk4', 'ivory2', 'ivory3', 'ivory4', 'honeydew2', 'honeydew3', 'honeydew4',
    'LavenderBlush2', 'LavenderBlush3', 'LavenderBlush4', 'MistyRose2', 'MistyRose3',
    'MistyRose4', 'azure2', 'azure3', 'azure4', 'SlateBlue1', 'SlateBlue2', 'SlateBlue3',
    'SlateBlue4', 'RoyalBlue1', 'RoyalBlue2', 'RoyalBlue3', 'RoyalBlue4', 'blue2', 'blue4',
    'DodgerBlue2', 'DodgerBlue3', 'DodgerBlue4', 'SteelBlue1', 'SteelBlue2',
    'SteelBlue3', 'SteelBlue4', 'DeepSkyBlue2', 'DeepSkyBlue3', 'DeepSkyBlue4',
    'SkyBlue1', 'SkyBlue2', 'SkyBlue3', 'SkyBlue4', 'LightSkyBlue1', 'LightSkyBlue2',
    'LightSkyBlue3', 'LightSkyBlue4', 'SlateGray1', 'SlateGray2', 'SlateGray3',
    'SlateGray4', 'LightSteelBlue1', 'LightSteelBlue2', 'LightSteelBlue3',
    'LightSteelBlue4', 'LightBlue1', 'LightBlue2', 'LightBlue3', 'LightBlue4',
    'LightCyan2', 'LightCyan3', 'LightCyan4', 'PaleTurquoise1', 'PaleTurquoise2',
    'PaleTurquoise3', 'PaleTurquoise4', 'CadetBlue1', 'CadetBlue2', 'CadetBlue3',
    'CadetBlue4', 'turquoise1', 'turquoise2', 'turquoise3', 'turquoise4', 'cyan2', 'cyan3',
    'cyan4', 'DarkSlateGray1', 'DarkSlateGray2', 'DarkSlateGray3', 'DarkSlateGray4',
    'aquamarine2', 'aquamarine4', 'DarkSeaGreen1', 'DarkSeaGreen2', 'DarkSeaGreen3',
    'DarkSeaGreen4', 'SeaGreen1', 'SeaGreen2', 'SeaGreen3', 'PaleGreen1', 'PaleGreen2',
    'PaleGreen3', 'PaleGreen4', 'SpringGreen2', 'SpringGreen3', 'SpringGreen4',
    'green2', 'green3', 'green4', 'chartreuse2', 'chartreuse3', 'chartreuse4',
    'OliveDrab1', 'OliveDrab2', 'OliveDrab4', 'DarkOliveGreen1', 'DarkOliveGreen2',
    'DarkOliveGreen3', 'DarkOliveGreen4', 'khaki1', 'khaki2', 'khaki3', 'khaki4',
    'LightGoldenrod1', 'LightGoldenrod2', 'LightGoldenrod3', 'LightGoldenrod4',
    'LightYellow2', 'LightYellow3', 'LightYellow4', 'yellow2', 'yellow3', 'yellow4',
    'gold2', 'gold3', 'gold4', 'goldenrod1', 'goldenrod2', 'goldenrod3', 'goldenrod4',
    'DarkGoldenrod1', 'DarkGoldenrod2', 'DarkGoldenrod3', 'DarkGoldenrod4',
    'RosyBrown1', 'RosyBrown2', 'RosyBrown3', 'RosyBrown4', 'IndianRed1', 'IndianRed2',
    'IndianRed3', 'IndianRed4', 'sienna1', 'sienna2', 'sienna3', 'sienna4', 'burlywood1',
    'burlywood2', 'burlywood3', 'burlywood4', 'wheat1', 'wheat2', 'wheat3', 'wheat4', 'tan1',
    'tan2', 'tan4', 'chocolate1', 'chocolate2', 'chocolate3', 'firebrick1', 'firebrick2',
    'firebrick3', 'firebrick4', 'brown1', 'brown2', 'brown3', 'brown4', 'salmon1', 'salmon2',
    'salmon3', 'salmon4', 'LightSalmon2', 'LightSalmon3', 'LightSalmon4', 'orange2',
    'orange3', 'orange4', 'DarkOrange1', 'DarkOrange2', 'DarkOrange3', 'DarkOrange4',
    'coral1', 'coral2', 'coral3', 'coral4', 'tomato2', 'tomato3', 'tomato4', 'OrangeRed2',
    'OrangeRed3', 'OrangeRed4', 'red2', 'red3', 'red4', 'DeepPink2', 'DeepPink3', 'DeepPink4',
    'HotPink1', 'HotPink2', 'HotPink3', 'HotPink4', 'pink1', 'pink2', 'pink3', 'pink4',
    'LightPink1', 'LightPink2', 'LightPink3', 'LightPink4', 'PaleVioletRed1',
    'PaleVioletRed2', 'PaleVioletRed3', 'PaleVioletRed4', 'maroon1', 'maroon2',
    'maroon3', 'maroon4', 'VioletRed1', 'VioletRed2', 'VioletRed3', 'VioletRed4',
    'magenta2', 'magenta3', 'magenta4', 'orchid1', 'orchid2', 'orchid3', 'orchid4', 'plum1',
    'plum2', 'plum3', 'plum4', 'MediumOrchid1', 'MediumOrchid2', 'MediumOrchid3',
    'MediumOrchid4', 'DarkOrchid1', 'DarkOrchid2', 'DarkOrchid3', 'DarkOrchid4',
    'purple1', 'purple2', 'purple3', 'purple4', 'MediumPurple1', 'MediumPurple2',
    'MediumPurple3', 'MediumPurple4', 'thistle1', 'thistle2', 'thistle3', 'thistle4',
    'gray1', 'gray2', 'gray3', 'gray4', 'gray5', 'gray6', 'gray7', 'gray8', 'gray9', 'gray10',
    'gray11', 'gray12', 'gray13', 'gray14', 'gray15', 'gray16', 'gray17', 'gray18', 'gray19',
    'gray20', 'gray21', 'gray22', 'gray23', 'gray24', 'gray25', 'gray26', 'gray27', 'gray28',
    'gray29', 'gray30', 'gray31', 'gray32', 'gray33', 'gray34', 'gray35', 'gray36', 'gray37',
    'gray38', 'gray39', 'gray40', 'gray42', 'gray43', 'gray44', 'gray45', 'gray46', 'gray47',
    'gray48', 'gray49', 'gray50', 'gray51', 'gray52', 'gray53', 'gray54', 'gray55', 'gray56',
    'gray57', 'gray58', 'gray59', 'gray60', 'gray61', 'gray62', 'gray63', 'gray64', 'gray65',
    'gray66', 'gray67', 'gray68', 'gray69', 'gray70', 'gray71', 'gray72', 'gray73', 'gray74',
    'gray75', 'gray76', 'gray77', 'gray78', 'gray79', 'gray80', 'gray81', 'gray82', 'gray83',
    'gray84', 'gray85', 'gray86', 'gray87', 'gray88', 'gray89', 'gray90', 'gray91', 'gray92',
    'gray93', 'gray94', 'gray95', 'gray97', 'gray98', 'gray99']

    colors=random.sample(color_list,1)
    turtle.color(colors)
    turtle.bgcolor("black")
    turtle.dot(y)

    if y==0:
     
        px=random.randrange(-300,300)
        py=random.randrange(-300,300)
        turtle.penup()
        turtle.setpos(px,py)
        y=random.randrange(0,150)



                
   
The loop returns with: 
 while True:
    try:
        print("Please enter password: ")
        x=input()
        password=int(x)
        print("Please enter correct password: ", password, "is not correct")
    except:
        print("password: " ,password, "is not correct")
        break    

>>> 
Please enter password: 
152
Please enter correct password:  152 is not correct
Please enter password: 

While loop return with the value from 14 to 1.
 x = 15
while x > 0:              
   x = x -1
   if x == 10:
      continue
   print("x value is equal :", x)

>>> 
x value is equal : 14
x value is equal : 13
x value is equal : 12
x value is equal : 11
x value is equal : 9
x value is equal : 8
x value is equal : 7
x value is equal : 6
x value is equal : 5
x value is equal : 4
x value is equal : 3
x value is equal : 2
x value is equal : 1
x value is equal : 0
>>> 



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