#!user/bin/python
#encoding:utf8

#while
time = 0
population = 1000 # 1000 bacteria to start with
grow_rate  = 0.21 # 21% growth per minute
while population < 2000:
    population = population + grow_rate * population
    print population
    time = time + 1
print "It took %d minutes for the bacteria to double." % time
print "...and the final population was %6.2f bacteria." % population

text = ' '
while text != "quit":
    text = raw_input("Please enter a chemical formula (or 'quit' to exit): ")
    if text == "quit":
        print "...exiting program."
    elif text == "H2O":
        print "Water"
    elif text == "NH3":
        print "Ammonia"
    elif text == "CH3":
        print "Methane"
    else:
        print "Unknown compound"

#break
earth_line = 1
file = open("data.txt","r")
for line in file:
    line = line.strip()
    if line == "Earth":
        break
    earth_line += 1
print "Earth is at the line %d" % earth_line
file.close()

#continue
entry_number = 1
file = open("data.txt","r")
for line in file:
    line = line.strip()
    if line.startswith('#'):
        continue
    if line == "Earth":
        break
    entry_number += 1
print "Earth is the %dth-lightest planet." % entry_number

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