Python code for Indian Mobile Number validation

validateIndianNumbers.py

'''
Indian Mobile Number validation criteria:

The Country calling code for india is +91 
valid pre-fixes are 0,91,+91 .
All mobile phone numbers are 10 digits long (not including a pre-fix). 
The first digit should contain number between 9,8,7 or 6.
Rest of the nine digits can be any number between 0 to 9.
'''

#function for validating
def ph_validate(num):
    
    country_code = '0'
    if(len(num)>10):
        country_code=num[:len(num)%10]
        num=num[len(num)%10:]
        
    first_digit=['6','7','8','9']
    valid_pre_fix=['0','91','+91']
    
    if(len(num)==10 and num.isdigit()):
        if(country_code in valid_pre_fix and num[0] in first_digit):
            return("Valid")
        else:
            return("Invalid")
    else:    
        return("Invalid")


#driver code
num=input("Enter the number : ")

result=ph_validate(num)

print(result)