Validate if all keys are present

class CustomException(Exception):
    pass

def validate_params(params, req_keys=[]):                                           
    """                                                                      
    Verify if all required keys are present in the dictionary passed   
    to this method

:param params: Parameter Dictionary to check
    :param req_keys: These Keys are required in the dictionary
    :rtype: Boolean                                                          
    :returns: True or False                                                  
    """                                                                      
    if all(_ in params for _ in req_keys):                       
        return True                                                          
    raise CustomException("Not all keys present in dictionary")
    
    
try:
    good = {'reqKey': 'yeahh', 'somethingelse': 'something'}
    result = validate_params(good, req_keys=['reqKey'])
    print(result)
except CustomException:
    print("Exception thrown")
    
    
try:
    bad = {'key1': 'value1'}
    result = validate_params(bad, req_keys=['reqKey'])
    print(result)
except CustomException:
    print("Exception thrown")

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