Define a function allEqual of type ''a list -> bool that will return true will all element in the input list are all equal, false otherwise. If the input list is empty or is a singleton list, the function should return true. For example,

Follows are the code to this question:

def allEqual(l):#defining a method allEqual that accepts a parameter  

   if len(l)==0:#defining if block that check list length equal to 0

       return True#return true value

   x=set(l) #defining x variable that set of given list

   if len(x)!=1: #defining if that check x is not equal to 1  

       return False#return False

   return True#return True

print(allEqual([]))#Use print method to call method and print value

print(allEqual(["aa"]))#Use print method to call method and print value  

print(allEqual(["aa", "aa", "aa"]))#Use print method to call method and print value  

print(allEqual(["aa", "aa", "ab"]))#Use print method to call method and print value

print(allEqual([1,1,3, 1]))#Use print method to call method and print value

Output:

True

True

True

False

False

Explanation:

In the above-given code a method "allEqual" is defined that accept and a list in its parameter and inside the method a conditional statement is used that can be defined as follows:

In if block, it checks the length of the list which is equal to 0, it will return 0.

In the next step, an "x" variable is declared, that uses the set method to hold list value and use if block to check length not equal to 1 and return false, or method returns a value that is equal to true.