An authentic vowel skewer is a skewer with a delicious and juicy mix of consonants and vowels. However, the way they are made must be just right:

• Skewers must begin and end with a consonant.
• Skewers must alternate between consonants and vowels.
• There must be an even spacing between each letter on the skewer, so that there is a consistent flavour throughout.

Create a function which returns whether a given vowel skewer is authentic.

Examples

is_authentic_skewer("B--A--N--A--N--A--S") ➞ true

is_authentic_skewer("A--X--E") ➞ false
# Should start and end with a consonant.

is_authentic_skewer("C-L-A-P") ➞ false
# Should alternate between consonants and vowels.

is_authentic_skewer("M--A---T-E-S") ➞ false
# Should have consistent spacing between letters.

Notes

• All tests will be given in uppercase.
• Strings without any actual skewer "-" or letters should return false.