def check_string(str1):
    
    messg = [
    lambda str1: any(x.isupper() for x in str1) or 'String must have 1 upper case character.',
    lambda str1: any(x.islower() for x in str1) or 'String must have 1 lower case character.',
    lambda str1: any(x.isdigit() for x in str1) or 'String must have 1 number.',
    lambda str1: len(str1) >= 7                 or 'String length should be atleast 8.',]
    result = [x for x in [i(str1) for i in messg] if x != True]
    if not result:
        result.append('Valid string.')
    return result  
def check_string(eD79):
    messg = [
        lambda eD79: any(x.isupper() for x in eD79)
        or "String must have 1 upper case character.",
        lambda eD79: any(x.islower() for x in eD79)
        or "String must have 1 lower case character.",
        lambda eD79: any(x.isdigit() for x in eD79) or "String must have 1 number.",
       
        lambda eD79: len(eD79) >= 7 or "String length should be atleast 8.",
    ]
    result = [x for x in [i(eD79) for i in messg] if x != True]
    if not result:
        result.append("Valid string.")
    return result