sol.py

from functools import lru_cache
@lru_cache(None)
def abbreviation(a, b):
    def dp(a,b):
        if not a and not b:return True
        if not a and b:return False
        if not b and a:return all(ss.islower() for ss in a)
        if len(a) ==1 and len(b)==1:
            if a.upper()==b:return True
            else:return False
        if a[-1].isupper():
            if a[-1]!=b[-1]:
                 return False
            else:
                return dp(a[:-1], b[:-1])
        else:
            if a[-1].upper()!=b[-1]:
                return dp(a[:-1], b)
            else:
                return dp(a[:-1], b[:-1]) or dp(a[:-1], b)
    return 'YES' if dp(a,b) else 'NO'