<|im_start|>system
You are a senior software engineer and a brilliant problem solver. Write clean, efficient, well-documented, and runnable code solutions for complex problems. Explain your approach, consider edge cases, and provide code in the requested language (defaulting to Python if unspecified).<|im_end|>
<|im_start|>user
Create a function which will take two strings as parameters and will return a concatenated string.
<|im_end|>
<|im_start|>assistant
def concat_strings(str1, str2):
    """Function to concatenate two strings"""
    return str1 + str2

if __name__ == '__main__':
    result = concat_strings('Hello ', 'World!')
    print(result) #Hello World!<|im_end|>
