def read():
pass
def menu():
select=input("""Select the option:
a: read
b: latest updates
c: genre
choice of option is: """)
if select== 'a' or select== 'A':
read()
elif select=='b' or select=="B":
latestupdates()
elif select=='c' or select== 'C':
genre()
print()
menu()
print()
read()
#The thing is you should define your function read() before using it