EscreverNumerosPorExtenso

def split(cdu):
    return [int(i) for i in cdu]
	
def splitInClasses(numero):
    
	size = len(numero)
	s = 0 if size % 3 == 0 else (3 - size % 3)
	num = '0' * s + numero
	lstClasses = [ num[i:i+3] for i in range(0,len(num),3)]
    
	return lstClasses

def removeEmptyElements(lstWords):
    name = []
    
    for i in lstWords:
        if i!='':
            name += [i]
    return name

def lerOrdens(cdu):
    
    
    dctNameNumbers = {0:['','',''],
           1:['um','dez','cento'],
           2:['dois','vinte','duzentos'], 
           3:['três','trinta','trezentos'], 
           4:['quatro','quarenta','quatrocentos'],
           5:['cinco', 'cinquenta', 'quinhentos'], 
           6:['seis','sessenta','seiscentos'],
           7:['sete','setenta','setecentos'], 
           8:['oito','oitenta','oitocentos'],
           9:['nove','noventa','novecentos'],
           11:['onze','doze','treze','quatorze','quinze', 'dezesseis', 'dezessete', 'dezoito', 'dezenove']}
    
    
    c, d, u = split(cdu)
    
    
    if 100*c+10*d+u == 100:
        return 'cem'
    
    elif 100*c+10*d+u == 0:
        return ''
    
    if 10*d+u>10 and 10*d+u < 20:
           name =  ' e '.join(removeEmptyElements([dctNameNumbers[c][2], dctNameNumbers[11][u-1]]))
                                                
    else:
           name =  ' e '.join(removeEmptyElements([dctNameNumbers[c][2], dctNameNumbers[d][1], dctNameNumbers[u][0]]))
       
    
    return name

def lerNumero(numero):
    #12 837
    name = ''
    dctNumber ={1:'', 2:'mil', 3:'milh', 4:'bilh', 5:'trilh', 6:'quatrilh', 7:'quintilh', 
                8:'sextilh'}
	
	
    lstClasses = splitInClasses(numero)
    s = len(lstClasses)
	
    for i in range(s,0,-1):
        name += ' e ' + lerOrdens(lstClasses[s-i]) + ' ' + dctNumber[i] 
    return name[3:]

print lerNumero('9723112931')

# for i in range(1000):
    # num = ('000'+str(i))[-3:]
	# print i , " ==> " , lerOrdens(num)

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