Python string have not control characters
Question: i have proxy string:

    
    
    proxy = '127.0.0.1:8080'
    

i need check is it real string:

    
    
    def is_proxy(proxy):
        return not any(c.isalpha() for c in proxy)
    

to skip string like:

    
    
    fail_proxy = 'This is proxy: 127.0.0.1:8080'
    

but some time i have like:

    
    
    fail_proxy2 = '127.0.0.1:8080\r'
    is_proxy(fail_proxy2) is True
    True
    

need False


Answer: Try the following specific approach using `re` module(regexp):

    
    
    import re
    
    def is_proxy(proxy):
        return re.fullmatch('^\d{1,3}\.\d{1,3}\.\d{1,3}.\d{1,3}:\d{1,5}$', proxy) is not None
    
    proxy1 = '127.0.0.1:8080'
    proxy2 = '127.0.0.1:8080\r'
    
    print(is_proxy(proxy1))   # True
    print(is_proxy(proxy2))   # False
    

As for port number (`\d{1,5}`): range **1-65535** are available for port
numbers

