BF long to shorthand

# python 3.4.3
# convert BF code to shorthand BF by by replacing 3 or more commands with a decimal number and the command
# in the form +++++ becomes 5+
#             ]]] becomes 3]

prevch=""
nextch=""
counter=1
total_count=0
command_set="<>+-[],."

file = open(input(("bf file: "), 'r')

print()

while True:
    nextch=file.read(1)

    if(not nextch):
        file.close()
        break

    if(nextch in command_set):

        total_count += 1

        if(nextch != prevch):
            if(counter == 1):
                print(prevch, end="")
            elif(counter == 2):
                print(prevch, end="")
                print(prevch, end="")
            else:
                print(counter, end="")
                print(prevch, end="")
            counter=1

        else:
            counter+=1

        prevch = nextch

if(counter == 1):
    print(prevch, end="")
elif(counter == 2):
    print(prevch, end="")
    print(prevch, end="")
else:
    print(counter, end="")
    print(prevch, end="")

print()
print()
print(total_count, "Commands")

"""
Sample input BF code, Hello World implementations from the Esoteric Programming Language Wiki
++++++++++[>+++++++>++++++++++>+++>+<
<<<-]>++.>+.+++++++..+++.>++.<<++++++
+++++++++.>.+++.------.--------.>+.>.

bf_l2s.py returns:

10+[>7+>10+>3+>+4<-]>++.>+.7+..3+.>++.<<15+.>.3+.6-.8-.>+.>.
111 Commands

bf_s2l.py returns the original program (without formatting), and it runs too!
"""