def removefirstlastchar(x):
	value = str(x)
	if value.lower() == 'NAN'.lower():
		return x
	if(value[0].isalpha() == True):
		value = value[1:]
	if(value[-1].isalpha() == True):
		value = value[:-1]
	return float(value) 
 
 
 
# I am passing the above function to the columns 74:92 in my dataframe
df.iloc[:, 74:92] = df.iloc[:, 74:92].apply(removefirstlastchar) 
 
# This is not cleaning. it says "could not convert string to float: '0     O15.5\\n1       NaN\\n2       NaN\\n3       NaN\\n4       NaN\\n5     15.4K\\n6       NaN\\n7       NaN\\n8       NaN\\n9       NaN\\n10      NaN\\n11      NaN\\n12      NaN\\n13      NaN\\n14      NaN\\n15      NaN\\n16    Q10.4\\n17      NaN\\n18      NaN\\n19      NaN\\n20      NaN\\n21      NaN\\n22      NaN\\n23    S16.7\\n24      NaN\\n25      NaN\\n26      NaN\\n27      NaN\\n28      NaN\\n29     14.5\\n30     14.3\\n31      NaN\\n32      NaN\\n33    14.6P\\n34      NaN\\n35      NaN\\n36      NaN\\nName: depression_adult, dtype: objec'", 'occurred at index depression_adult')
 
 

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