abc = "Hello World"
message = "Hello Python!"
print(message)
print('a' + 'b')  # Concatenation
print(message[0])  # Indexing
print(len(message))  # Length of a string
str1 = "Hello"
str2 = " World"
print(str1 + str2)
str3 = str1 + str2
print(str3)
print(str3.count('l'))
print(str3.index('l'))
print(str3[0:10])  # String slicing
print(str3[-1])
print(str3[-1:])
print(str3[::])
print(str3.lower())
print(str3.upper())
print(str3.index('l'))
print(str3.rindex('l'))
print(str3.find("Wor"))
str3 = str3.replace("World", "Python")
print(str3)
print(str('123'))
