# Start: 4pm
# End: 7pm
# 3h

fin = open("fin.txt", 'r')
fot = open("fot.txt", 'w')

for line in fin:
    fl = line.strip().split(': ')

    # ["Start", "4pm"]
    # ["End", "7pm"]
    # ["3h"]
    fot.write(fl[-1])
    fot.write(fl[0])

fot.close()
fin.close()

#4pmStart7pmEnd3h3h

fot = open("fot.txt", 'r')
a = fot.read(3) # "4pm"
fot.seek(8)
print(a, fot.read())
fot.close()
#4pm 7pmEnd3h3h