# $7$

# Find the length of the given string.

# Extract the first character $\text{'}$T$\text{'}$ from the given string using the index and assign it to a variable.

# Extract the substring $\text{'}$CQS$\text{'}$ from the given string using string slicing and assign it to a variable.

# Loop through the string to print each character in it$.$

# Using find$()$ method, check if $\text{'}311\text{'}$ exists in the given string.

# Using replace$()$ method, replace the word 'Lab' with 'class' in the given string.