Puzzle-Vijeen

#vijeen's puzzle
f=open("input","r")
FullText=f.read()
FullText=FullText.split()
NumberOfLines=len(FullText)
LineLength=len(FullText[0])
output=''
for i in range (0,NumberOfLines):
    for j in range (3,LineLength-3):
        if FullText[i][j].islower():
            if FullText[i][j-1].isupper() and FullText[i][j-2].isupper() and FullText[i][j-3].isupper():
                if FullText[i][j+1].isupper() and FullText[i][j+2].isupper() and FullText[i][j+3].isupper():
                    if j!=3 and j+3!=LineLength-1:
                        if FullText[i][j-4].islower() and FullText[i][j+4].islower():
                            output=output+FullText[i][j-3]+FullText[i][j-2]+FullText[i][j-1]+FullText[i][j]+FullText[i][j+1]+FullText[i][j+2]+FullText[i][j+3]+'\n'
                    elif j==3 and FullText[i][j+4].islower():
                        output=output+FullText[i][j-3]+FullText[i][j-2]+FullText[i][j-1]+FullText[i][j]+FullText[i][j+1]+FullText[i][j+2]+FullText[i][j+3]+'\n'
                    elif j+3==LineLength-1 and FullText[i][j-4].islower():
                        output=output+FullText[i][j-3]+FullText[i][j-2]+FullText[i][j-1]+FullText[i][j]+FullText[i][j+1]+FullText[i][j+2]+FullText[i][j+3]+'\n'

print(output)