Determine whether the string

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All strings judgment 
isdigit whether all digital 
whether all the letters isalpha returns True 
if isalnum letters and numbers 
if islower all lowercase 
whether isupper all capital letters 
if istitle are capitalized the first letter of the English alphabet 
isalpha whether all English Chinese characters will be sentenced to True 

if isspace only whitespace 
whether isnumeric only by a digital algorithm in the title role of composition is relatively large 
character or string of characters isprintable whether all strings are printable 
isdecimal whether contains a decimal character only 
if a valid identifier isidentifier Python is used to determine whether a valid variable names 
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